Sun Country and Allegiant plan major new leisure airline merger deal

Rhea-AI Filing Summary

Sun Country Airlines Holdings plans to combine with Allegiant to create a larger, more competitive leisure-focused U.S. airline. The companies expect to close the transaction in the second half of 2026, subject to customary closing conditions, including regulatory and shareholder approvals. Sun Country notes that Allegiant has committed to maintain its significant presence in Minneapolis–St. Paul, that there will be no immediate changes to the Sun Country brand, and that because the merger is designed to increase the size of the airline, it does not expect reductions to front-line positions. Management emphasizes cultural fit, future growth opportunities for employees, and extensive forward-looking risk factors, including regulatory outcomes, integration challenges, costs, business disruption, and potential dilution from Allegiant issuing additional shares of common stock.

Insights

Airline M&A and regulatory analyst

Sun Country plans a merger with Allegiant, with benefits framed but significant regulatory, integration and dilution risks highlighted.

The transaction would combine Sun Country with Allegiant to form a larger leisure-focused U.S. airline. Management frames the deal as a strategic step to better compete with larger carriers, increase route breadth and passenger volumes, and create more internal career opportunities. Leadership continuity appears partly preserved, as Sun Country’s CEO expects to serve as an advisor and join Allegiant’s board after closing.

The closing is targeted for the second half of 2026, explicitly conditioned on regulatory and shareholder approvals and other customary conditions. The text stresses that Allegiant will maintain Sun Country’s significant Minneapolis–St. Paul presence, that the Sun Country brand will remain unchanged initially, and that no reductions in front-line positions are expected because the combined airline is designed to be larger.

The risk discussion is extensive. It cites potential termination of the merger agreement, legal proceedings and related costs, failure or delay in obtaining regulatory or stockholder approvals, and the chance that expected benefits, cost savings, synergies or growth are delayed, more costly, or not realized. It also flags integration complexity, business disruption during the pendency of the deal, reputational risk with customers, employees and unions, and potential dilution from Allegiant issuing additional common shares to fund the transaction. Overall, this is a clearly material strategic event, but its financial impact will depend heavily on regulatory outcomes and post-merger execution.

FORM OF 425 FILING (PRIOR TO FILING OF FORM S-4)

FILED BY SUN COUNTRY AIRLINES HOLDINGS, INC.

PURSUANT TO RULE 425 UNDER THE SECURITIES ACT OF 1933

AND DEEMED FILED PURSUANT TO RULE 14a-12

UNDER THE SECURITIES EXCHANGE ACT OF 1934

SUBJECT COMPANY: SUN COUNTRY AIRLINES HOLDINGS, INC.

COMMISSION FILE NO. 001-40217

Subject Line: Important Announcement – Sun Country Airlines is combining with Allegiant

Team Sun Country,

We have just announced [HYPERLINK TO PR] that we are combining with Allegiant to create a leading, more competitive leisure-focused U.S. airline.

We have been deliberate and thoughtful in building toward this announcement. I have shared with you that we are always looking for opportunities to better compete with big airlines, and I could not be more confident that this is the right transaction with the right partner at the right time for Sun Country.

Our people are the most important part of this combination. As a bigger, more diversified company with more routes and more passengers, there will be more opportunities for our teams to grow. Allegiant has committed to maintain our significant presence in Minneapolis-St. Paul and there will be no immediate changes to the Sun Country brand. Since the merger is designed to increase the size of the airline, we do not expect any reductions to front-line positions.

I know you have questions about what comes next and what this announcement means for you. We do not have all of the answers today, but I encourage you to read the FAQs below [HYPERLINK], watch this video [HYPERLINK], as well as this video from me and Allegiant’s CEO, Greg Anderson, [HYPERLINK]. We will also be hosting a virtual Town Hall meeting Monday morning at 9:30 AM CT – link to join [HYPERLINK].

From the outset, it was clear that Allegiant values our people, brand, deep roots in Minnesota and position as one of the nation’s most respected low-cost, leisure carriers. We will only continue to grow with Allegiant – here’s why:

• Increased MSP service. We have continuously increased our share of MSP since 2018. Combining and growing our network with Allegiant will strengthen our position by adding service from MSP to destinations where Allegiant has a presence.

• Better serving passengers through expanded network and reach. The combined company will serve 22 million annual passengers with service to nearly 175 cities and more than 650 routes, a fleet of 195 aircraft and a more robust loyalty program. With our highly complementary networks, we expect Allegiant will be able to expand nonstop service from its small and mid-sized cities to our international destinations in Mexico, Central America, Canada and the Caribbean.

• Better serving charter and cargo customers. Our charter and cargo business is a core differentiator that Allegiant intends to grow thanks to the expanded resources to come from this combination; something we could not do as effectively on our own.

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Having spent much of my career at Allegiant, I am confident this is a strong cultural fit. Both Sun Country and Allegiant teams have immense pride in their work with a shared commitment to delivering affordable travel experiences without compromising the quality of the journey. I am looking forward to serving as an advisor to Greg Anderson and as a member of Allegiant’s Board once the transaction closes.

We will soon form a joint integration team with members from Sun Country and Allegiant to begin planning for how best to bring the two companies together. In the coming days and weeks, you will also hear directly from Greg Anderson and have the opportunity to learn more about Allegiant’s business. We will continue to update you.

As we move through the approval process, it is critical that we remain focused on execution and delivering for our customers. We expect to close the transaction in the second half of 2026, subject to the completion of customary closing conditions, including regulatory and shareholder approvals.

This is a monumental day for all of us. Thank you for the hard work that has enabled us to enter this combination from a place of strength and momentum. I look forward to seeing you during the Town Hall tomorrow.

- Jude

Note: Consistent with company policy, do not discuss this with any reporter or media. Refer any outside inquiries from members of the media to mediarelations@suncountry.com.

Note: Employees are reminded to follow the social media policy in the employee handbook and to refrain from posting about this news in a way that suggests they are speaking on behalf of the company.

Cautionary Statement Regarding Forward-Looking Statements

This communication contains forward-looking statements under the safe harbor provisions of Section 21E of the Securities Exchange Act of 1934, Section 27A of the Securities Act of 1933 and the Private Securities Litigation Reform Act of 1995. Forward-looking statements include all statements that are not historical facts and often can be identified by the use of forward-looking terminology such as the words “believe,” “expect,” “guidance,” “anticipate,” “intend,” “plan,” “estimate”, “project”, “hope” or similar expressions. Forward-looking statements in this communication are based on Allegiant’s and Sun Country’s current expectations, estimates and projections about the expected date of closing of the proposed transaction and the potential benefits thereof, their respective businesses and industries, management’s beliefs and certain assumptions made by Allegiant and Sun Country, all of which are subject to change. Forward-looking statements in this communication may relate to, without limitation, the benefits of the proposed transaction, including future financial and operating results; the parties’ respective plans, objectives, expectations and intentions; the expected timing and likelihood of completion of the proposed transaction; expected synergies of the proposed transaction; the timing and result of various regulatory proceedings related to the proposed transaction; the ability to execute and finance current and long-term business, operational, capital expenditures and growth plans and strategies; the impact of increased or increasing transaction and financing costs associated with the proposed transaction or otherwise, as well as inflation and interest rates; and the ability to access debt and equity capital markets.

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Forward-looking statements involve risks, uncertainties and assumptions that could cause actual results to differ materially from those expressed in any forward-looking statements. Accordingly, there are or will be important factors that could cause actual results to differ materially from those indicated in such statements and, therefore, you should not place undue reliance on any such statements and caution must be exercised in relying on forward-looking statements. Important risk factors that may cause such a difference include, but are not limited to, the following: the occurrence of any event, change or other circumstance that could give rise to the right of one or both of the parties to terminate the definitive merger agreement for the proposed transaction; the risk that potential legal proceedings may be instituted against Allegiant or Sun Country and result in significant costs of defense, indemnification or liability; the possibility that the proposed transaction does not close when expected or at all because required stockholder approvals, required regulatory approvals or other conditions to closing are not received or satisfied on a timely basis or at all (and the risk that such regulatory approvals may result in the imposition of conditions that could adversely affect the combined company or the expected benefits of the proposed transaction); the risk that the combined company will not realize expected benefits, cost savings, accretion, synergies and/or growth from the proposed transaction or that any of the foregoing may take longer to realize or be more costly to achieve than expected; disruption to the parties’ businesses as a result of the announcement and pendency of the proposed transaction; the costs associated with the anticipated length of time of the pendency of the proposed transaction, including the restrictions contained in the definitive merger agreement on the ability of each of Sun Country and Allegiant to operate their respective businesses outside the ordinary course consistent with past practice during the pendency of the proposed transaction; the diversion of Allegiant’s or Sun Country’s respective management teams’ attention and time from ongoing business operations and opportunities on acquisition-related matters; the risk that the integration of Sun Country’s operations will be materially delayed or will be more costly or difficult than expected or that Allegiant is otherwise unable to successfully integrate Sun Country’s businesses into its businesses; the possibility that the proposed transaction may be more expensive to complete than anticipated, including as a result of unexpected factors or events; reputational risk and potential adverse reactions of Allegiant’s or Sun Country’s customers, suppliers, employees, labor unions or other business partners, including those resulting from the announcement or completion of the proposed transaction; the dilution caused by Allegiant’s issuance of additional shares of its common stock in connection with the consummation of the proposed transaction; a material adverse change in the business, condition or results of operations of Allegiant or Sun Country; changes in domestic or international economic, political or business conditions, including those impacting the airline industry (including customers, employees and supply chains); Allegiant’s and Sun Country’s ability to successfully implement their respective operational, productivity and strategic initiatives; the outcome of claims, litigation, governmental proceedings and investigations involving Allegiant or Sun Country; and a cybersecurity incident or other disruption to Sun Country’s or Allegiant’s technology infrastructure.

Forward-looking statements in this communication are qualified by and should be read together with, the risk factors set forth above and the risk factors included in Allegiant’s and Sun Country’s respective annual and quarterly reports as filed with the Securities and Exchange Commission (the “SEC”), and readers should refer to such risks, uncertainties and risk factors in evaluating such forward-looking statements. In addition, the risk factors discussed above are not exhaustive and they, along with other risk factors, will be more fully discussed in the registration statement and joint proxy statement/prospectus to be filed with the SEC in connection with the proposed transaction.

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The forward-looking statements in this communication are made only as of the date they were first issued, and unless otherwise required by applicable securities laws, Allegiant and Sun Country disclaim any intention or obligation to update or revise any forward-looking statements, whether as a result of new information, future events, or otherwise.

Important Additional Information and Where to Find It

In connection with the proposed transaction, Allegiant intends to file with the SEC a registration statement on Form S-4 (the “Registration Statement”), which will include a prospectus with respect to the shares of Allegiant’s common stock to be issued in the proposed transaction and a joint proxy statement for Allegiant’s and Sun Country’s respective stockholders (the “Joint Proxy Statement/Prospectus”). The definitive joint proxy statement (if and when available) will be mailed to stockholders of Allegiant and Sun Country. Each of Allegiant and Sun Country may also file with or furnish to the SEC other relevant documents regarding the proposed transaction. This communication is not a substitute for the Registration Statement, the Joint Proxy Statement/Prospectus or any other document that Allegiant or Sun Country may file with the SEC or send to their respective stockholders in connection with the proposed transaction. INVESTORS AND SECURITY HOLDERS OF ALLEGIANT AND SUN COUNTRY ARE URGED TO READ THE REGISTRATION STATEMENT AND THE JOINT PROXY STATEMENT/PROSPECTUS INCLUDED WITHIN THE REGISTRATION WHEN THEY BECOME AVAILABLE, AS WELL AS ANY OTHER RELEVANT DOCUMENTS FILED WITH THE SEC IN CONNECTION WITH THE PROPOSED TRANSACTION OR INCORPORATED BY REFERENCE INTO THE REGISTRATION STATEMENT AND THE JOINT PROXY STATEMENT/PROSPECTUS (INCLUDING ANY AMENDMENTS OR SUPPLEMENTS THERETO), BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION REGARDING ALLEGIANT, SUN COUNTRY, THE PROPOSED TRANSACTION AND RELATED MATTERS. Investors and security holders of Allegiant and Sun Country may obtain free copies of these documents and other documents filed with the SEC by Allegiant or Sun Country through the website maintained by the SEC at http://www.sec.gov or from Allegiant at its website, https://ir.allegiantair.com/financials/sec-filings/default.aspx, or from Sun Country at its website, https://ir.suncountry.com/financials/sec-filings. Documents filed with the SEC by Allegiant will be available free of charge by accessing Allegiant’s website at https://ir.allegiantair.com/financials/sec-filings/default.aspx, or alternatively by directing a request by mail to Allegiant’s Investor Relations department, 1201 North Town Center Drive, Las Vegas, NV 89144, and documents filed with the SEC by Sun Country will be available free of charge by accessing Sun Country’s website at https://ir.suncountry.com/financials/sec-filings, or alternatively by directing a request by mail to Sun Country’s Investor Relations department, 2005 Cargo Road, Minneapolis, MN 55450.

Participants In The Solicitation

Allegiant, Sun Country and certain of their respective directors and executive officers may be deemed to be participants in the solicitation of proxies from the stockholders of Allegiant and Sun Country in connection with the proposed transaction under the rules of the SEC.

Information about the interests of the directors and executive officers of Allegiant and Sun Country and other persons who may be deemed to be participants in the solicitation of stockholders of Allegiant and Sun Country in connection with the proposed transaction and a description of their direct and indirect interests, by security holdings or otherwise, will be included in the Joint Proxy Statement/Prospectus, which will be filed with the SEC.

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Information about the directors and executive officers of Allegiant, their ownership of Allegiant common stock and Allegiant’s transactions with related persons can also be found in the Allegiant Annual Report and Allegiant’s definitive proxy statement in connection with its 2025 annual meeting of stockholders, as filed with the SEC on Schedule 14A on April 30, 2025 (the “Allegiant 2025 Proxy Statement”), and other documents subsequently filed by Allegiant with the SEC, which are available on its website, https://ir.allegiantair.com/financials/sec-filings/default.aspx. Such information is set forth in the sections entitled “Proposal No. 1 – Election of Directors”, “Proposal No. 2 – Advisory (non-binding) Vote on Executive Compensation”, “Proposal No. 3 – Approval of Amendment to Allegiant 2022 Long-Term Incentive Plan to Increase Number of Shares Available”, “Executive Compensation” and “Related Party Transactions” of the Allegiant 2025 Proxy Statement. To the extent holdings of Allegiant common stock by the directors and executive officers of Allegiant have changed from the amounts of Allegiant common stock held by such persons as reflected therein, such changes have been or will be reflected on Statements of Change in Ownership on Form 4 filed with the SEC, which are available at https://www.sec.gov/edgar/browse/?CIK=1362468&owner=exclude under the tab “Ownership Disclosures”.

Information about the directors and executive officers of Sun Country, their ownership of Sun Country common stock and Sun Country’s transactions with related persons can also be found in the definitive proxy statement for Sun Country’s 2025 annual meeting of stockholders, as filed with the SEC on Schedule 14A on April 25, 2025 (which is available at https://ir.suncountry.com/financials/sec-filings), and other documents subsequently filed by Sun Country with the SEC. Such information is set forth in the sections entitled “Proposal 1– Reelection of Directors”, “Proposal 2 – Non-binding (Advisory) Vote to Approve the Compensation of Our Named Executive Officers”, “Executive Compensation”, “Certain Relationships and Related Person Transactions” and “Security Ownership of Certain Beneficial Owners and Management” of such definitive proxy statement. Please also refer to Sun Country’s subsequent Current Reports, as filed with the SEC on Form 8-K on September 22, 2025 (which is available at https://ir.suncountry.com/financials/sec-filings) and on October 30, 2025, regarding subsequent changes to Sun Country’s Board of Directors and executive management following the filing of such definitive proxy statement. To the extent holdings of Sun Country common stock by the directors and executive officers of Sun Country have changed from the amounts of Sun Country common stock held by such persons as reflected in the definitive proxy statement, such changes have been or will be reflected on Statements of Change in Ownership on Form 4 filed with the SEC, which are available at https://www.sec.gov/edgar/browse/?CIK=1743907&owner=exclude under the tab “Ownership Disclosures”.

Free copies of these documents may be obtained as described above.

No Offer or Solicitation

This communication is for informational purposes only and does not constitute, or form a part of, an offer to sell or the solicitation of an offer to sell or an offer to buy or the solicitation of an offer to buy any securities, and there shall be no sale of securities, in any jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such jurisdiction. No offer of securities shall be made except by means of a prospectus meeting the requirements of Section 10 of the Securities Act of 1933, as amended, and otherwise in accordance with applicable law.

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FAQ

What did Sun Country Airlines (SNCY) announce in this communication?

Sun Country Airlines announced that it plans to combine with Allegiant to create a larger, more competitive leisure-focused U.S. airline. The communication describes this as a significant strategic transaction and a “monumental day” for the company.

When is the Sun Country and Allegiant merger expected to close?

The companies state that they expect to close the transaction in the second half of 2026, subject to the completion of customary closing conditions, including required regulatory and shareholder approvals.

How will the merger affect Sun Country employees and front-line positions?

Sun Country emphasizes that its people are central to the combination and that, because the merger is designed to increase the size of the airline, it does not expect reductions to front-line positions. Management also highlights anticipated more opportunities for teams to grow in a bigger, more diversified company.

What happens to the Sun Country brand and its Minneapolis–St. Paul presence?

Allegiant has committed to maintain Sun Country’s significant presence in Minneapolis–St. Paul, and the communication notes there will be no immediate changes to the Sun Country brand. Employees are told the companies will form a joint integration team to plan how to bring the two businesses together.

What key risks and uncertainties are associated with the Sun Country–Allegiant merger?

The forward-looking statements section lists numerous risks, including the possibility the merger agreement could be terminated, failure or delay in obtaining stockholder and regulatory approvals, higher-than-expected transaction and financing costs, integration challenges, disruption to ongoing business, reputational impacts, and dilution from Allegiant’s issuance of additional common shares. It also cites broader economic and industry conditions and potential cybersecurity or operational disruptions.

Is this Sun Country communication an offer to buy or sell securities?

No. The communication explicitly states that it is for informational purposes only and does not constitute an offer to sell or a solicitation of an offer to buy any securities. It clarifies that no offer of securities will be made except by means of a prospectus that meets the requirements of Section 10 of the Securities Act of 1933 and applicable law.

What additional documents will be filed in connection with the Sun Country and Allegiant transaction?

Allegiant intends to file a registration statement on Form S-4 with the SEC, which will include a prospectus for the Allegiant common stock to be issued and a joint proxy statement/prospectus for Allegiant and Sun Country stockholders. Investors are urged to read the registration statement and joint proxy statement/prospectus when available, as they will contain important information about the companies and the proposed transaction.