SUMMARY

The following summary highlights some of the information contained in this joint proxy statement/prospectus. This summary may not contain all of the information that is important to you. For a more complete description of the merger agreement, the mergers and the other transactions contemplated by the merger agreement, MAA and Colonial encourage you to read carefully this entire joint proxy statement/prospectus, including the attached Annexes and the other documents to which we have referred you because this section does not provide all the information that might be important to you with respect to the mergers and the other matters being considered at the applicable special meeting. See also the section entitled “Where You Can Find More Information” beginning on page 205. We have included page references to direct you to a more complete description of the topics presented in this summary.

The Companies

Mid-America Apartment Communities, Inc. (See page 46)

MAA is a Tennessee corporation that has elected to be taxed as a REIT under the Code. MAA owns, acquires, renovates, develops and manages apartment communities in the Sunbelt region of the United States. As of June 30, 2013, MAA owned or owned interests in a total of 163 multifamily apartment communities comprising 49,017 apartments located in 13 states, including four communities comprising 1,156 apartments owned through MAA’s joint venture, Mid-America Multifamily Fund II, LLC. MAA also had two development communities under construction totaling 564 units as of June 30, 2013. Four of MAA’s properties include retail components with approximately 107,000 square feet of gross leasable area.

MAA’s most significant asset is its ownership interest in Mid-America Apartments, L.P., or MAA LP, a Tennessee limited partnership. MAA LP and its subsidiaries conduct the operations of a substantial majority of MAA’s business, hold a substantial majority of MAA’s consolidated assets and generate a substantial majority of MAA’s revenues. MAA is the sole general partner of MAA LP and, as of June 30, 2013, owned 40,141,197 common units of partnership interest, or approximately 95.9% of the outstanding partnership interests of MAA LP. Prior to the effective times of the mergers, MAA will contribute all of its assets, with the exception of its ownership interest in MAA LP and certain bank accounts held by MAA, to MAA LP, and as a result, MAA will be structured as a traditional umbrella partnership REIT, or UPREIT.

MAA common stock is listed on the NYSE, trading under the symbol “MAA.”

MAA was incorporated in the state of Tennessee in 1993, and MAA LP was formed in the state of Tennessee in 1993. MAA’s principal executive offices are located at 6584 Poplar Avenue, Memphis, Tennessee 38138, and its telephone number is (901) 682-6600. MAA had 1,384 full-time employees and 62 part-time employees as of December 31, 2012.

Martha Merger Sub, LP, or OP Merger Sub, an indirect wholly-owned subsidiary of MAA LP, is a Delaware limited partnership formed on May 30, 2013 for the purpose of effecting the partnership merger. Upon completion of the partnership merger, OP Merger Sub will be merged with and into Colonial LP, with Colonial LP surviving as an indirect wholly-owned subsidiary of MAA LP. OP Merger Sub has not conducted any activities other than those incidental to its formation and the matters contemplated by the merger agreement.

Colonial Properties Trust (See page 46)

Colonial, originally formed as a Maryland REIT on July 9, 1993 and reorganized as an Alabama REIT under the Alabama REIT statute on August 21, 1995, is a self-administered REIT that has elected to be taxed as a REIT under the Code. Colonial is a multifamily-focused self-administered and self-managed equity REIT, which

means that it is engaged in the acquisition, development, ownership, management and leasing of multifamily apartment communities and other commercial real estate properties. As of June 30, 2013, Colonial owned or maintained a partial ownership in a total of 115 multifamily apartment communities comprising 34,577 apartments located in 11 states and Colonial had seven commercial properties with approximately 1,194,000 square feet of gross leasable area.

Colonial’s only material asset is its ownership of limited partnership interests in Colonial Realty Limited Partnership, or Colonial LP, a Delaware limited partnership formed in 1993. Colonial LP and its subsidiaries conduct all of Colonial’s business, hold all of Colonial’s consolidated assets and generate all of Colonial’s revenues. Colonial is the sole general partner of Colonial LP and, as of June 30, 2013, owned approximately 92.5% of the outstanding partnership interests of Colonial LP.

Colonial common shares are listed on the NYSE, trading under the symbol “CLP.”

Colonial’s principal executive offices are located at 2101 Sixth Avenue North, Suite 750, Birmingham, Alabama 35203, and its telephone number is (205) 250-8700. Colonial had 911 employees as of December 31, 2012.

The Combined Corporation (See page 47)

The Combined Corporation will be named “Mid-America Apartment Communities, Inc.” and will be a Tennessee corporation that is a self-administered REIT, which has elected to be taxed as a REIT under the Code. The Combined Corporation will be a Sunbelt-focused, publicly traded, multifamily REIT with enhanced capabilities to deliver value for residents, shareholders and employees. The Combined Corporation is expected to have a pro forma equity market capitalization of approximately $5.4 billion, and a total market capitalization in excess of $8.7 billion as of June 30, 2013. The Combined Corporation’s asset base will consist primarily of approximately 85,000 multifamily units in 285 properties. The Combined Corporation will maintain strategic diversity across large and secondary markets within the high growth Sunbelt region of the United States. The Combined Corporation’s ten largest markets will be Dallas/Ft. Worth, Atlanta, Austin, Raleigh, Charlotte, Nashville, Jacksonville, Tampa, Orlando and Houston.

The business of the Combined Corporation will be operated through MAA LP and its subsidiaries and will be structured as a traditional UPREIT. On a pro forma basis giving effect to the mergers, the Combined Corporation will own an approximate 94.6% partnership interest in MAA LP and, as its sole general partner, the Combined Corporation will have the full, exclusive and complete responsibility for and discretion in the day-to-day management and control of MAA LP.

The common stock of the Combined Corporation will be listed on the NYSE, trading under the symbol “MAA.”

The Combined Corporation’s principal executive offices will be located at 6584 Poplar Avenue, Memphis, Tennessee 38138, and its telephone number will be (901) 682-6600.

The Mergers

The Merger Agreement (See page 151)

MAA, MAA LP, OP Merger Sub, Colonial and Colonial LP have entered into the merger agreement attached as Annex A to this joint proxy statement/prospectus, which is incorporated herein by reference. MAA and Colonial encourage you to carefully read the merger agreement in its entirety because it is the principal document governing the merger and the other transactions contemplated by the merger agreement.

The Mergers (See page 68)

Subject to the terms and conditions of the merger agreement, at the effective time of the parent merger, Colonial will merge with and into MAA, which is referred to herein as the parent merger, with MAA surviving the parent merger, which is referred to herein as the Combined Corporation. The shares of common stock of the Combined Corporation are expected to be listed and traded on the NYSE under the symbol “MAA.” The merger agreement also provides for the merger, prior to the parent merger, of OP Merger Sub, a subsidiary of MAA LP, with and into Colonial LP with Colonial LP continuing as the surviving entity and an indirectly wholly owned subsidiary of MAA LP, which is referred to herein as the partnership merger, and, together with the parent merger, are referred to herein as the mergers.

Upon completion of the parent merger, we estimate that continuing MAA equity holders will own approximately 56% of the issued and outstanding common shares of the Combined Corporation, assuming the conversion of all limited partnership units of MAA LP held by existing limited partners of MAA LP to shares of Combined Corporation common stock, and former Colonial equity holders will own approximately 44% of the issued and outstanding shares of common stock of the Combined Corporation, assuming the conversion to shares of Combined Corporation common stock of all limited partnership units issued by MAA LP to former limited partners of Colonial LP.

The Merger Consideration (See page 152)

In the parent merger, each Colonial common share (other than shares with respect to which dissenters’ rights have been properly exercised and not withdrawn under applicable law) issued and outstanding immediately prior to the effective time of the parent merger will be converted into the right to receive 0.360 shares of MAA common stock. The exchange ratio is fixed and will not be adjusted for changes in the market value of MAA common stock or Colonial common shares. Because of this, the implied value of the consideration to be received by Colonial shareholders in the parent merger will fluctuate between now and the completion of the mergers. Based on MAA’s closing price of $67.97 per share on May 31, 2013, the last trading day before the announcement of the proposed merger, the exchange ratio represented approximately $24.47 in MAA common stock for each Colonial common share. Based on MAA’s closing price of $62.26 per share on August 20, 2013, the latest practicable trading day before the date of this joint proxy statement/prospectus, the exchange ratio represented approximately $22.41 in MAA common stock for each Colonial common share.

You are urged to obtain current market prices of shares of MAA common stock and Colonial common shares. You are cautioned that the trading price of the common stock of the Combined Corporation after the mergers may be affected by factors different from those currently affecting the trading prices of MAA common stock and Colonial common shares, and therefore, the historical trading prices of MAA and Colonial may not be indicative of the trading price of the Combined Corporation. See the risks related to the mergers and the related transactions described under the section “Risk Factors—Risk Factors Relating to the Mergers” beginning on page 32.

Voting Agreements (See page 172)

Concurrently with the execution of the merger agreement, Colonial and Colonial LP entered into separate Voting Agreements with H. Eric Bolton, Jr., MAA’s Chairman and Chief Executive Officer, W. Reid Sanders, a member of the MAA Board, and another shareholder of MAA who is not a director or officer of MAA, and MAA and MAA LP entered into separate Voting Agreements with Thomas H. Lowder, James K. Lowder and Harold W. Ripps, each members of the Colonial Board. As of August 20, 2013, the MAA directors and shareholders who are a party to a Voting Agreement with Colonial and Colonial LP collectively owned approximately 0.36% of the outstanding shares of MAA common stock and approximately 37.37% of the outstanding limited partnership units in MAA LP, and the Colonial trustees who are a party to a Voting Agreement with MAA and

MAA LP collectively owned approximately 3.9% of the outstanding Colonial common shares and approximately 3.5% of the outstanding limited partnership units in Colonial LP (including the limited partnership units held by Colonial).

Pursuant to the terms of the Voting Agreements, each of the shareholder parties thereto has agreed, subject to the terms and conditions contained in each Voting Agreement, to among other things, vote all of his shares of MAA common stock, Colonial common shares, limited partnership units in MAA LP or, in the event of any vote by limited partners of Colonial LP, limited partnership units in Colonial LP, as applicable, whether currently owned or acquired at any time prior to the termination of the applicable Voting Agreement, in favor of the mergers and against any other Acquisition Proposal (as defined in the “The Merger Agreement—Covenants and Agreements—No Solicitation of Transactions” on page 160) for MAA or Colonial, as applicable, any action or agreement that would reasonably be expected to result in any condition to the consummation of the mergers not being fulfilled, and any action that could reasonably be expected to impede or materially adversely affect consummation of the transactions contemplated by the merger agreement.

Each of the shareholder parties to the Voting Agreements has also agreed to comply with certain restrictions on the transfer of his shares subject to the Voting Agreement. Each Voting Agreement entered into with MAA shareholders terminates upon the earliest to occur of: (1) the later to occur of (A) the approval and adoption of the merger agreement at the MAA special meeting, and (B) the approval of the merger agreement by the holders of limited partnership units in MAA LP; and (2) the termination of the merger agreement pursuant to its terms. Each Voting Agreement entered into with Colonial shareholders terminates upon the earliest to occur of: (1) the approval and adoption of the merger agreement at the Colonial special meeting; and (2) the termination of the merger agreement pursuant to its terms.

The foregoing summary of the Voting Agreements is subject to, and qualified in its entirety by reference to, the full text of each of the Voting Agreements. Copies of the Forms of Voting Agreement are attached as Annex C and Annex D to this joint proxy statement/prospectus and are incorporated herein by reference. For more information see “Voting Agreements” beginning on page 172.

Recommendation of the MAA Board (See page 88)

After careful consideration, the MAA Board has unanimously determined and declared that the merger agreement, the parent merger and the other transactions contemplated by the merger agreement, including the issuance of shares of MAA common stock to Colonial shareholders in the parent merger, which is collectively referred to herein as the MAA merger proposal, are advisable and in the best interests of MAA and its shareholders and unanimously adopted and approved the merger agreement, the parent merger and the other transactions contemplated by the merger agreement. The MAA Board unanimously recommends that MAA shareholders vote FOR the MAA merger proposal, FOR the proposal to approve the MAA 2013 Stock Incentive Plan and FOR the proposal to approve one or more adjournments of the special meeting, if necessary or appropriate, including adjournments to permit further solicitation of proxies in favor of approval and adoption of the merger agreement and the parent merger.

Recommendation of the Colonial Board (See page 92)

After careful consideration, and based in part on the unanimous recommendation of the transaction committee of the Colonial Board, the Colonial Board unanimously (i) determined that the parent merger (including the plan of merger) and the other transactions contemplated by the merger agreement are advisable and in the best interests of Colonial and its shareholders, (ii) approved and adopted the merger agreement and the plan of merger, (iii) directed that a proposal to approve and adopt the merger agreement and the parent merger pursuant to the plan of merger be submitted for consideration at a meeting of Colonial’s shareholders and (iv) recommended the approval and adoption of the merger agreement and the parent merger pursuant to the plan

of merger by Colonial’s shareholders. The Colonial Board unanimously recommends that Colonial shareholders vote FOR the proposal to approve and adopt the merger agreement, the parent merger pursuant to plan of merger and the other transactions contemplated by the merger agreement, FOR the proposal to approve, on an advisory (non-binding) basis, the compensation payable to certain executive officers of Colonial in connection with the mergers, and FOR the proposal to approve one or more adjournments of the Colonial special meeting, if necessary or appropriate, including adjournments to permit further solicitation of proxies in favor of approval and adoption of the merger agreement, the parent merger pursuant to the plan of merger and the other transactions contemplated by the merger agreement.

Summary of Risk Factors Related to the Merger (See page 32)

You should consider carefully all of the risk factors together with all of the other information included in this joint proxy statement/prospectus before deciding how to vote. The risks related to the mergers and the related transactions are described under the section “Risk Factors—Risk Factors Relating to the Mergers” beginning on page 32.

The MAA Special Meeting (See page 48)

The MAA special meeting will be held at MAA corporate headquarters, 6584 Poplar Avenue, Memphis, Tennessee 38138, on September 27, 2013, at 9:00 a.m., Central Daylight Time.

At the MAA special meeting, MAA shareholders will be asked to consider and vote upon the following matters:

Approval of the MAA merger proposal requires the affirmative vote of holders of a majority of the outstanding shares of MAA common stock.

Approval of the MAA 2013 Stock Incentive Plan requires the votes cast “FOR” the proposal exceed the votes cast “AGAINST” the proposal.

Approval of the adjournment of the MAA special meeting requires the votes cast “FOR” the proposal exceed the votes cast “AGAINST” the proposal.

At the close of business on the record date, directors and executive officers of MAA and their affiliates were entitled to vote 302,780 shares of MAA common stock, or approximately 0.71% of the shares of MAA common stock issued and outstanding on that date. Messrs. Bolton and Sanders have entered into voting agreements that obligate them to vote “FOR” the MAA merger proposal. Additionally, MAA currently expects that the other MAA directors and executive officers will vote their shares of MAA common stock in favor of the MAA merger proposal as well as the other proposals to be considered at the MAA special meeting, although none of them is obligated to do so.

Your vote as a MAA shareholder is very important. Accordingly, please sign and return the enclosed proxy card whether or not you plan to attend the MAA special meeting in person.

The Colonial Special Meeting (See page 60)

The Colonial special meeting will be held in the conference center on the 1^st floor of the Colonial Brookwood Center, 569 Brookwood Village, Suite 131, Homewood, Alabama 35209 on September 27, 2013 at 10:30 a.m., Central Daylight Time.

At the Colonial special meeting, Colonial shareholders will be asked to consider and vote upon the following matters:

Approval and adoption of the merger agreement, the parent merger pursuant to the plan of merger and the other transactions contemplated by the merger agreement, will require the affirmative vote of the holders of at least a majority of the Colonial common shares outstanding as of the record date for the Colonial special meeting.

Approval, on an advisory (non-binding) basis, of the compensation payable to certain executive officers of Colonial in connection with the mergers will require the affirmative vote of the holders of a majority of the Colonial common shares present in person or represented by proxy at the Colonial special meeting and entitled to vote on this proposal. An abstention from voting on this proposal will have the same effect as voting against this proposal.

Approval of one or more adjournments of the Colonial special meeting, if necessary or appropriate, including adjournments to permit further solicitation of proxies in favor of approval and adoption of the merger agreement and the parent merger pursuant to the plan of merger, will require the affirmative vote of the holders of a majority of the Colonial common shares present in person or represented by proxy at the Colonial special meeting and entitled to vote on this proposal.

At the close of business on the record date, trustees and executive officers of Colonial and their affiliates were entitled to vote 5,909,185 Colonial common shares, or approximately 6.7% of the Colonial common shares issued and outstanding on that date. Messrs. T. Lowder, J. Lowder and Ripps have entered into voting agreements that obligate them to vote “FOR” the Colonial merger proposal. Additionally, Colonial currently expects that the other Colonial trustees and executive officers will vote their Colonial common shares in favor of the Colonial merger proposal as well as the other proposals to be considered at the Colonial special meeting, although none of them is obligated to do so.

Your vote as a Colonial shareholder is very important. Accordingly, please sign and return the enclosed proxy card whether or not you plan to attend the Colonial special meeting in person.

Opinions of Financial Advisors

Opinion of MAA’s Financial Advisor (See page 98)

J.P. Morgan Securities LLC, which we refer to herein as J.P. Morgan, rendered its oral opinion, subsequently confirmed in writing, to the MAA Board that, as of June 1, 2013, and based upon and subject to the factors and assumptions set forth in its opinion, the exchange ratio of 0.360 provided for in the parent merger was fair, from a financial point of view, to MAA. The full text of the written opinion of J.P. Morgan dated June 1, 2013, which sets forth the assumptions made, matters considered and limits on the review undertaken, is attached as Annex F to this joint proxy statement/prospectus and is incorporated herein by reference. You are urged to read the opinion in its entirety. J.P. Morgan’s written opinion is addressed to the MAA Board, is directed only to the exchange ratio in the parent merger and does not constitute a recommendation to any shareholder of MAA as to how such shareholder should vote at the MAA special meeting. The summary of the opinion of J.P. Morgan set forth in this joint proxy statement/prospectus is qualified in its entirety by reference to the full text of such opinion.

See “The Parent Merger—Opinion of MAA’s Financial Advisor” beginning on page 98.

Opinion of Colonial’s Financial Advisor (See page 104)

Colonial’s financial advisor, Merrill Lynch, Pierce, Fenner & Smith Incorporated, referred to as BofA Merrill Lynch, delivered a written opinion, dated June 2, 2013, to the Colonial Board as to the fairness, from a financial point of view and as of such date, to the holders of Colonial common shares of the exchange ratio provided for in the parent merger. The full text of BofA Merrill Lynch’s written opinion, dated June 2, 2013, is attached as Annex G to this joint proxy statement/prospectus and sets forth, among other things, the assumptions made, procedures followed, factors considered and limitations on the review undertaken by BofA Merrill Lynch in rendering its opinion. BofA Merrill Lynch delivered its opinion to the Colonial Board for the benefit and use of the Colonial Board (in its capacity as such) in connection with and for purposes of its evaluation of the exchange ratio provided for in the parent merger from a financial point of view. BofA Merrill Lynch’s opinion did not address any other aspect of the mergers and no opinion or view was expressed as to the relative merits of the mergers in comparison to other strategies or transactions that might be available to Colonial or in which Colonial might engage or as to the underlying business decision of Colonial to proceed with or effect the mergers. BofA Merrill Lynch also expressed no opinion or recommendation as to how any shareholder should vote or act in connection with the mergers or any other matter.

See “The Parent Merger—Opinion of Colonial’s Financial Advisor” beginning on page 104.

Treatment of the Colonial Equity Incentive Plans (See page 153)

At the effective time of the parent merger, the Combined Corporation will assume all outstanding options, whether or not exercisable, and restricted share awards subject to their current terms under the Colonial equity incentive plans, as adjusted for the exchange ratio. Each option so assumed by the Combined Corporation will continue to have the same terms and conditions (including vesting schedule) as were applicable under the Colonial equity incentive plans prior to the effective time of the parent merger

As of the effective time of the parent merger, all Colonial common shares subject to vesting and other restrictions under the Colonial equity incentive plans will convert into the right to receive shares of Combined Corporation common stock that are subject to the same vesting conditions and other terms and conditions as are applicable to such shares of Colonial restricted shares immediately prior to the effective time of the parent merger, as adjusted for the exchange ratio.

See “The Merger Agreement—Merger Consideration; Effects of the Parent Merger and the Partnership Merger—Assumption of Colonial Equity Incentive Plans by MAA” beginning on page 153.

Directors and Management of MAA After the Mergers (See page 152)

Immediately following the effective time of the parent merger, the MAA Board will be increased to 12 members, with the seven current MAA directors, H. Eric Bolton, Jr., Alan B. Graf, Jr., Ralph Horn, Philip W. Norwood, W. Reid Sanders, William B. Sansom and Gary Shorb, continuing as directors of the Combined Corporation. Alan B. Graf, Jr. and Ralph Horn, Co-Lead Independent Directors for MAA, will serve as Co-Lead Independent Directors for the Combined Corporation. The MAA Board will fill the five newly created vacancies by immediately appointing to the MAA Board the five members designated by the Colonial Board, Thomas H. Lowder, James K. Lowder, Claude B. Nielsen, Harold W. Ripps and John W. Spiegel, which members are referred to herein as the Colonial designees, to serve until the 2014 annual meeting of MAA’s shareholders (and until their successors have been duly elected and qualified). The Colonial designees will be nominated by the MAA Board for reelection at the 2014 and 2015 annual meetings of MAA’s shareholders, in all cases subject to the satisfaction and compliance of such Colonial designees with MAA’s then-current corporate governance guidelines and code of business conduct and ethics.

Certain of the executive officers of MAA immediately prior to the effective time of the mergers will continue as the executive officers of the Combined Corporation following the effective time of the mergers.

Interests of MAA’s Directors and Executive Officers in the Mergers (See page 117)

In considering the recommendation of the MAA Board to approve the parent merger and the other transactions contemplated by the merger agreement, MAA shareholders should be aware that certain executive officers and directors of MAA have certain interests in the mergers that may be different from, or in addition to, the interests of MAA shareholders generally. These interests may create potential conflicts of interest. The MAA Board was aware of those interests and considered them, among other matters, in reaching its decision to approve the merger agreement and the transactions contemplated thereby.

Interests of Colonial’s Trustees and Executive Officers in the Mergers (See page 118)

In considering the recommendation of the Colonial Board to approve and adopt the merger agreement, the parent merger pursuant to the plan of merger and the other transactions contemplated by the merger agreement, Colonial shareholders should be aware that executive officers and trustees of Colonial have certain interests in

the mergers that may be different from, or in addition to, the interests of Colonial shareholders generally. These interests may create potential conflicts of interest. The Colonial Board was aware of those interests and considered them, among other matters, in reaching its decision to approve and adopt the merger agreement, the parent merger pursuant to the plan of merger and the transactions contemplated by the merger agreement.

Listing of Shares of the Combined Corporation Common Stock; Delisting and Deregistration of Colonial Common Shares (See page 148)

It is a condition to the completion of the mergers that the shares of MAA common stock issuable in connection with the parent merger be approved for listing on the NYSE, subject to official notice of issuance. After the parent merger is completed, the Colonial common shares currently listed on the NYSE will cease to be listed on the NYSE and will be deregistered under the Exchange Act.

Shareholder Dissenters’ Rights in the Parent Merger (See page 177)

Each shareholder of an Alabama real estate investment trust has the same appraisal rights as a shareholder of an Alabama business corporation under the Alabama Business Corporation Law, or the ABCL, holders of Colonial common shares are entitled to dissent and demand payment for their shares at “fair value” plus accrued interest. See “Dissenters’ Rights” beginning on page 177. MAA’s obligation to close the mergers will be conditioned on holders of no more than 15% of Colonial common shares properly perfecting their right to dissent and demand cash payment for their shares.

Conditions to Completion of the Mergers (See page 165)

A number of conditions must be satisfied or waived, where legally permissible, before the mergers can be consummated. These include, among others:

As of the date of this joint proxy statement/prospectus, all of the third party consents and approvals required as a condition to the obligation of the parties to complete the mergers as described in the final bullet point above had been obtained and not rescinded.

Neither MAA nor Colonial can give any assurance as to when or if all of the conditions to the consummation of the mergers will be satisfied or waived or that the mergers will occur.

For more information regarding the conditions to the consummation of the mergers and a complete list of such conditions, see “The Merger Agreement—Conditions to Completion of the Mergers” beginning on page 165.

Regulatory Approvals Required for the Mergers (See page 124)

MAA and Colonial are not aware of any material federal or state regulatory requirements that must be complied with, or approvals that must be obtained, in connection with the mergers or the other transactions contemplated by the merger agreement. See “The Parent Merger—Regulatory Approvals Required for the Mergers” beginning on page 124.

No Solicitation and Change in Recommendation (See page 160)

Under the merger agreement, each of MAA and Colonial has agreed it will not, nor will it permit any of its subsidiaries to, authorize or permit any of its officers, trustees, directors or employees, and will use its reasonable best efforts to cause its and its subsidiaries’ representatives not to, directly or indirectly, (i) initiate, solicit or knowingly encourage or knowingly facilitate any inquiries or the making of any proposal or offer by or with a third party with respect to an Acquisition Proposal, (ii) engage in any negotiations concerning, or provide any confidential information or data to any person relating to an Acquisition Proposal, or knowingly facilitate any effort or attempt to make or implement an Acquisition Proposal, (iii) approve or execute or enter into any letter of intent, agreement in principle, merger agreement, asset purchase or share exchange agreement, option agreement or other similar agreement related to any Acquisition Proposal, or (iv) propose publicly or agree to do any of the foregoing.

However, prior to the approval of the parent merger and the other transactions contemplated by the merger agreement by their respective shareholders, each of MAA and Colonial may, under certain specified circumstances, engage in discussions or negotiations with and provide nonpublic information regarding itself to a third party making an unsolicited, bona fide written competing Acquisition Proposal. Under the merger agreement, Colonial is required to notify MAA promptly, and MAA is required to notify Colonial promptly, if it receives any Acquisition Proposal or inquiry or any request for nonpublic information in connection with an Acquisition Proposal.

Before the approval of the mergers and the other transactions contemplated by the merger agreement by their respective shareholders, each of the MAA Board and the Colonial Board may, under certain specified circumstances, withdraw its recommendation to its shareholders with respect to the merger if it determines in good faith, after consultation with outside legal counsel, that failure to take such action would be inconsistent with the directors’ or trustees’, as applicable, duties under applicable law. For more information regarding the limitations on MAA, the MAA Board, Colonial and the Colonial Board to consider other Acquisition Proposals, see “The Merger Agreement—Covenants and Agreements—No Solicitation of Transactions” beginning on page 160.

Termination of the Merger Agreement (See page 168)

The merger agreement may be terminated at any time before the effective time of the partnership merger by the mutual consent of MAA and Colonial in a written instrument, which action must be taken or authorized by the MAA Board and the Colonial Board.

In addition, either MAA or Colonial (so long as they are not at fault) may decide to terminate the merger agreement if (provided such action must be taken or authorized by the MAA Board or the Colonial Board, as applicable):

MAA may also decide to terminate the merger agreement if:

Colonial has reciprocal termination rights with respect to the merger agreement as MAA described above.

For more information regarding the rights of MAA and Colonial to terminate the merger agreement, see “The Merger Agreement—Termination of the Merger Agreement” beginning on page 168.

Termination Fee and Expenses (See page 169)

Generally, all fees and expenses incurred in connection with the mergers and the transactions contemplated by the merger agreement will be paid by the party incurring those fees and expenses. However, if the merger agreement is terminated because either party fails to obtain the approval of its shareholders, among other reasons, such party will be required to pay the other party reasonable documented out-of-pocket expenses actually incurred up to a maximum of $10 million. In certain other circumstances, either MAA or Colonial may be obligated to pay the other a termination fee of $75 million plus reasonable documented out-of-pocket expenses actually incurred up to a maximum of $10 million.

For more information regarding the termination fee and expense reimbursement, see “The Merger Agreement—Termination of the Merger Agreement—Termination Fee and Expenses Payable by Colonial to MAA” beginning on page 169 and “The Merger Agreement—Termination of the Merger Agreement—Termination Fee and Expenses Payable by MAA to Colonial” beginning on page 170.

Litigation Relating to the Mergers (See page 149)

On June 19, 2013, a putative class action lawsuit was filed in the Circuit Court for Jefferson County, Alabama against Colonial and purportedly on behalf of a proposed class of all Colonial shareholders captioned Williams v. Colonial Properties Trust, et al. (the “State Litigation”). A derivative claim purportedly on behalf of Colonial was also asserted in the State Litigation. The complaint names as defendants Colonial, the members of the Colonial board of trustees, Colonial LP, MAA, MAA LP and OP Merger Sub and alleges that the Colonial trustees breached their fiduciary duties by engaging in an unfair process leading to the merger agreement, failing to secure and obtain the best price reasonable for Colonial shareholders, allowing preclusive deal protection devices in the merger agreement, and by engaging in conflicted actions. The complaint alleges that Colonial LP, MAA, MAA LP and OP Merger Sub aided and abetted those breaches of fiduciary duties. The complaint seeks a declaration that the defendants have breached their fiduciary duties or aided and abetted such breaches and that the merger agreement is unlawful and unenforceable, an order enjoining the consummation of the mergers, direction of the Colonial trustees to exercise their fiduciary duties to obtain a transaction that is in the best interests of Colonial, rescission of the mergers in the event they are consummated, an award of costs and disbursements, including reasonable attorneys’ and experts’ fees, and other relief.

On July 2, 2013, plaintiff moved for expedited fact discovery and for an expedited schedule for filing and hearing a preliminary motion to enjoin the mergers; on July 11, 2013, defendants opposed those motions and moved to stay fact discovery. On July 11, 2013, defendants also moved to dismiss the complaint for failure to state a claim upon which relief can be granted on the grounds that: (1) the claims against the Colonial trustees are derivative and not direct, and plaintiff did not comply with Alabama law on serving notice of the claims on Colonial prior to filing; and (2) Alabama law does not recognize a cause of action in aiding and abetting a breach of fiduciary duty and, even if it did, such claims would also be derivative and not direct. The Court scheduled a motions hearing for August 8, 2013, which was continued on the request of the parties to the State Litigation to August 14, 2013 to facilitate settlement discussions. In the meantime, on August 2, 2013, plaintiff filed an amended complaint that re-asserted plaintiff’s earlier claims and added a new claim that the Colonial trustees breached their alleged duty of candor by not providing Colonial shareholders full and complete disclosures regarding the merger.

On August 14, 2013, prior to the Court’s scheduled hearing, the parties to the State Litigation reached an agreement in principle to settle the State Litigation, in which (a) defendants agreed to make certain additional

disclosures in this joint proxy statement/prospectus, and (b) the parties agreed that they would use their best efforts to agree upon, execute and present to the Court a stipulation of settlement which would, among other things, (i) provide for the conditional certification of a non-opt out settlement class pursuant to Alabama Rules of Civil Procedure 23(b)(1) and (b)(2) consisting generally of all record and beneficial holders of the common stock of Colonial from June 3, 2013 through and including the date of the closing of the parent merger (the “Settlement Class”); (ii) release all claims that members of the Settlement Class may have that were alleged in the State Litigation or otherwise arising out of or relating in any manner to the parent merger (except Colonial shareholders’ statutory dissenters’ rights, see “Dissenters’ Rights” beginning on page 177), and (iii) dismiss the State Litigation with prejudice. The proposed settlement also provides that the defendants will not oppose a request to the Court by plaintiff’s counsel for attorney’s fees up to an immaterial amount agreed to by the parties and is subject to, among other things, confirmatory discovery, agreement to a stipulation of settlement, and final court approval following notice to the Settlement Class. The parties reported the proposed settlement to the Court on August 14, 2013, and the Court ordered a stay of all proceedings (except those related to settlement). Colonial and MAA management believe that the allegations in the amended complaint are without merit and that the disclosures made prior to the settlement are adequate under the law but wish to settle the State Litigation in order to avoid the cost and distraction of further litigation. In the event that the stipulation of settlement is not approved by the Court, the defendants intend to vigorously defend the State Litigation.

On August 20, 2013, a purported Colonial shareholder filed an individual lawsuit in the United States District Court for the Northern District of Alabama against Colonial captioned Kempen v. Colonial Properties Trust, et al. (the “Federal Litigation”). The complaint names as defendants Colonial, the members of the Colonial board of trustees, Colonial LP, MAA, MAA LP and OP Merger Sub, and alleges that all defendants violated Section 14(a) of the Exchange Act and Rule 14a-9 promulgated thereunder because the joint proxy statement/prospectus included in the registration statement on Form S-4 filed with the SEC on July 19, 2013 is allegedly materially misleading, depriving plaintiff of making a fully informed decision regarding his vote on the parent merger. The complaint alleges that defendants misrepresented or omitted material facts concerning Colonial’s projections, the financial analyses of Colonial’s financial advisor, conflicts of interest affecting defendants and Colonial’s financial advisor, and the process employed by the Colonial trustees leading up to the decision to approve and recommend the parent merger. Plaintiff seeks an order enjoining the consummation of the mergers, rescission of the mergers in the event they are consummated or awarding Plaintiff rescissory damages, and an award of costs and disbursements, including reasonable attorneys’ and experts’ fees. Colonial and MAA management believe that the allegations in the complaint are without merit and intend to vigorously defend the Federal Litigation.

Material U.S. Federal Income Tax Consequences of the Parent Merger (See page 125)

Colonial and MAA intend that the parent merger of Colonial with and into MAA will qualify as a reorganization within the meaning of Section 368(a) of the Code. The closing of the parent merger is conditioned on the receipt by each of MAA and Colonial of an opinion from its respective counsel to the effect that the parent merger will qualify as a reorganization within the meaning of Section 368(a) of the Code. Assuming that the parent merger qualifies as a reorganization, U.S. holders of Colonial common shares generally will not recognize gain or loss for U.S. federal income tax purposes upon the receipt of Combined Corporation common stock in exchange for Colonial common shares in connection with the parent merger, except with respect to cash received in lieu of fractional shares of Combined Corporation common stock.

For further discussion of the material U.S. federal income tax consequences of the parent merger and the ownership of common stock of the Combined Corporation, see “The Parent Merger—Material U.S. Federal Income Tax Consequences of the Parent Merger” beginning on page 125.

Holders of Colonial common shares should consult their tax advisors to determine the tax consequences to them (including the application and effect of any state, local or non-U.S. income and other tax laws) of the parent merger.

Accounting Treatment of the Mergers (See page 147)

MAA prepares its financial statements in accordance with accounting principles generally accepted in the United States, which we refer to as GAAP. The parent merger will be accounted for by applying the acquisition method. See “The Parent Merger—Accounting Treatment.”

Comparison of Rights of Shareholders of MAA and Shareholders of Colonial (See page 186)

If the parent merger is consummated, shareholders of Colonial will become shareholders of MAA. The rights of Colonial shareholders are currently governed by and subject to the provisions of the Alabama Real Estate Investment Trust Law, or the AREITL, and the declaration of trust and bylaws of Colonial. Upon consummation of the parent merger, the rights of the former Colonial shareholders who receive MAA common stock will be governed by the Tennessee Business Corporation Act, or the TBCA, and the MAA charter and MAA bylaws, rather than the declaration of trust and bylaws of Colonial.

For a summary of certain differences between the rights of MAA shareholders and Colonial shareholders, see “Comparison of Rights of Shareholders of MAA and Shareholders of Colonial” beginning on page 186.

Selected Historical Financial Information of MAA

The following table sets forth selected consolidated financial information for MAA. The selected statement of income data for each of the years in the five-year period ended December 31, 2012 and the selected balance sheet data as of December 31 for each of the years in the five-year period ended December 31, 2012 have been derived from MAA’s audited consolidated financial statements incorporated herein by reference. The selected statement of income data for the six months ended June 30, 2013 and 2012 and the selected balance sheet data as of June 30, 2013 have been derived from MAA’s unaudited consolidated financial statements incorporated herein by reference. The following information should be read together with MAA’s Annual Report on Form 10-K for the year ended December 31, 2012, MAA’s Quarterly Report on Form 10-Q for the quarter ended June 30, 2013, and the other information that MAA has filed with the SEC and incorporated herein by reference. See “Where You Can Find More Information” beginning on page 205.