NYSE: SUI

In the UK, our communities are referred to as "holiday parks" and are located predominantly at irreplaceable seaside destinations in the south of England. We sell homes to holiday homeowners who lease a pitch at one of our properties through a site fee license arrangement. In addition, we sell new and pre-owned homes to current and prospective customers, and provide vacation opportunities to individuals and families complemented by high-quality amenities.

As of December 31, 2025, we owned and operated, directly or indirectly, or had an interest in, a portfolio of 513 developed properties located in the U.S., Canada, and the UK, including 294 MH communities, 166 RV communities, and 53 UK communities. As of December 31, 2025, the properties contained an aggregate of 178,650 developed sites comprised of 100,150 developed MH sites, 33,330 annual RV sites (inclusive of both annual and seasonal usage rights), 23,550 transient RV sites, 17,750 UK annual sites, and 3,870 UK transient RV sites.

Our executive and principal property management office is located at 27777 Franklin Road, Suite 300, Southfield, Michigan 48034, and our telephone number is (248) 208-2500. Our Park Holidays principal office is located in Bexhill-on-Sea, East Sussex, UK. We have regional property management offices throughout the U.S. We employed an aggregate of 3,614 full and part time employees as of December 31, 2025.

Our website address is www.suninc.com and we make available, free of charge, on or through our website all of our periodic reports, including our Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q, and current reports on Form 8-K, as soon as reasonably practicable after we file such reports with the SEC. Additionally, the SEC maintains a website at https://www.sec.gov, that contains reports, proxy information statements, and other information about us.

SAFE HARBOR SALE

From 2020 through 2024, we were in the business of operating, acquiring, developing, and expanding marinas through our Safe Harbor Marinas, LLC subsidiary ("Safe Harbor"). In February 2025, we entered into a definitive agreement to sell Safe Harbor for an aggregate purchase price of approximately $5.65 billion, subject to certain adjustments (the "Safe Harbor Sale"). During the three months ended June 30, 2025, we completed the initial closing of the Safe Harbor Sale, which generated approximately $5.25 billion of pre-tax cash proceeds, net of transaction costs. The subsequent closing of the transfer of subsidiaries owning 15 of Safe Harbor's properties (the "Delayed Consent Subsidiaries") with an aggregate agreed value of approximately $250.0 million was further subject to the receipt of certain third-party consents. Subsequent to the initial closing through June 30, 2025, we completed the sale of six Delayed Consent Subsidiaries for $136.7 million. On August 29, 2025, we completed the closing of the final nine Delayed Consent Subsidiaries for $117.5 million and fully divested our investment in the Safe Harbor business. In connection with the Safe Harbor Sale, we recorded a gain of $1.5 billion during the year ended December 31, 2025. The Safe Harbor Sale accelerates our strategy of focusing on our core business. Refer to Part II, Item 7, "Liquidity And Capital Resources," and Note 2, "Assets Held for Sale and Discontinued Operations," in our accompanying Consolidated Financial Statements for additional information related to Safe Harbor and the Safe Harbor Sale.

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REPORTABLE SEGMENTS

As a result of the Safe Harbor Sale, we have revised our reporting structure from a four-segment to a three-segment structure, which consists of (i) MH communities, (ii) RV communities, and (iii) communities in the UK. Additional information required by this item is incorporated herein by reference to the narrative and tabular description of segments and operating results under Item 7, "Management's Discussion and Analysis of Financial Condition and Results of Operations" and Note 10, "Segment Reporting," in our accompanying Consolidated Financial Statements.

STRUCTURE OF THE COMPANY

The Company is a REIT and the general partner of the Operating Partnership. As the sole general partner of the Operating Partnership, we generally have the power to manage and have complete control over the conduct of the Operating Partnership's affairs, and all decisions or actions made or taken by us as the general partner pursuant to the partnership agreement are generally binding upon all of the partners and the Operating Partnership.

The Operating Partnership is structured as an umbrella partnership REIT ("UPREIT"). We conduct substantially all of our operations through the Operating Partnership, which, directly or indirectly through other subsidiaries, owns substantially all of our assets. This UPREIT structure enables us to comply with certain complex requirements under the federal tax rules and regulations applicable to REITs, and to acquire properties in transactions that defer some or all of the sellers' tax consequences. The financial results of the Operating Partnership and our other subsidiaries are consolidated in our Consolidated Financial Statements. The financial results of the Operating Partnership include certain activities that do not necessarily qualify as REIT activities under the Internal Revenue Code of 1986, as amended (the "Code"). We have formed taxable REIT subsidiaries, as defined in the Code, to engage in such activities. We use taxable REIT subsidiaries to offer certain services to our residents and engage in activities that would not otherwise be permitted under the REIT rules if provided directly by us or by the Operating Partnership. The taxable REIT subsidiaries include our home sales business, SHS, which provides manufactured home sales, leasing, and other services to current and prospective tenants of our properties. Currently, all of our UK operations are conducted through taxable REIT subsidiaries.

Under the partnership agreement, the Operating Partnership is structured to make distributions with respect to certain of the Operating Partnership units ("OP units") at the same time that distributions are made to our common shareholders. The Operating Partnership is structured to permit limited partners holding certain classes or series of OP units to exchange those OP units for shares of our common stock (in a taxable transaction) and achieve liquidity for their investment.

As of December 31, 2025, we owned 95.7% of the OP Units and the limited partners of the Operating Partnership own the rest. The following table sets forth:

•The various series of OP units and the number of units of each series outstanding as of December 31, 2025;

•The relative ranking of the various series of OP units with respect to rights to the payment of distributions and the distribution of assets in the event of any voluntary or involuntary liquidation, dissolution, or winding up of the Operating Partnership;

•The number of shares of our common stock issuable upon the exchange, directly or indirectly, of each OP unit of the applicable series;

•Information regarding the annual distribution rate and terms of redemption rights for each series of OP units, as applicable.

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RankingDescription
OP Units Outstanding at December 31, 2025

Exchange Rate(1)

Annual Distribution Rate(2)

Cash Redemption(3)
Redemption Period

1Series A-1 preferred OP units169,913 2.43906.0 %N/AN/A

2Series C preferred OP units292,436 1.11005.0 %N/AN/A

3Series D preferred OP units488,958 0.80004.0 %Holder's OptionAny time

4Series E preferred OP units80,000 0.68975.5 %N/AN/A

5Series F preferred OP units70,000 0.62503.0 %Holder's OptionAny time

6Series G preferred OP units4,898 0.64523.2 %Holder's OptionAny time

7Series H preferred OP units560,968 0.60983.0 %Holder's OptionAny time

8Series J preferred OP units236,000 0.60612.85 %Holder's OptionDuring the 30-day period following a change of control of the Company or any time after April 21, 2026

9Series K preferred OP units1,000,000
0.5882(4)
4.0 %Holder's OptionWithin 60 days after March 23, 2028

10Series L preferred OP units20,000
0.6250(5)
3.5 %N/AN/A

11Series A-3 preferred OP units40,268 1.86054.5 %N/AN/A

12Common OP units
126,124,022(6)
1.0000Same distribution rate for common stock and common OP unitsN/AN/A

(1)Exchange rates are subject to adjustment upon stock splits, recapitalizations, and similar events. The exchange rates of certain series of OP units are approximated to four decimal places. Subject to certain limitations, holders can convert certain series of OP units to shares of our common stock and to common OP units at any time.

(2)Except for Common OP units, distributions are payable on the issue price of each OP unit, which is $100.00 per unit for all these preferred OP units.

(3)The redemption price for each preferred OP unit redeemed will be equal to its issue price plus all accrued but unpaid distributions.

(4)Each Series K preferred OP unit is exchangeable for 0.5882 common OP units. Each such common OP unit will be exchangeable for one share of our common stock. We have the right to cause the holders of Series K preferred OP units to exchange such units into common OP units at the applicable exchange rate (a) within 60 days after March 23, 2028 or (b) if at any time the trading price of our common stock for each of the preceding 60 trading days is equal to or greater than 120% of the Series K conversion price of $170 (as it may be adjusted under the Operating Partnership's partnership agreement). If in connection with an exchange pursuant to clause (a) above the recent average price of our common stock (as determined under the Operating Partnership's partnership agreement) is less than the Series K conversion price, we will be required to make an additional cash payment in respect of each exchanged Series K preferred OP unit equal to the product of (i) the Series K exchange rate and (ii) the difference between such average price and the Series K conversion price.

(5)Each Series L preferred OP unit is exchangeable for 0.6250 common OP units. Each such common OP unit will be exchangeable for one share of our common stock. We have the right to cause the holders of Series L preferred OP units to exchange such units into common OP units at the applicable exchange rate (a) any time after December 31, 2028 or (b) if at any time the trading price of our common stock for each of the preceding 60 trading days is equal to or greater than 120% of the Series L conversion price of $160 (as it may be adjusted under the Operating Partnership's partnership agreement). If in connection with an exchange pursuant to clause (a) above the recent average price of our common stock (as determined under the Operating Partnership's partnership agreement) is less than the Series L conversion price, we will be required to make an additional cash payment in respect of each exchanged Series L preferred OP unit equal to the product of (i) the Series L exchange rate and (ii) the difference between such average price and the Series L conversion price.

(6)Of the 126,124,022 Common OP units, 123,486,747 or 97.9% were held by us, and 2,637,275 or 2.1% were owned by various limited partners.

REAL PROPERTY OPERATIONS AND COMPETITION

MH and RV Segments

An MH community is a residential subdivision with sites for the placement of manufactured homes, related improvements, and amenities. Our MH communities are designed to offer affordable housing to individuals and families, while also providing a number of lifestyle amenities. Manufactured homes are detached single-family homes that are produced off-site by manufacturers and installed on site within the community. Manufactured homes are available in a wide array of designs, providing owners with a level of customization generally unavailable in multi-family housing complexes. Modern MH communities contain improvements similar to other garden-style residential developments, including centralized entrances, paved streets, curbs, gutters, and parkways.

An RV community is a resort with sites for the placement of RVs for varied lengths of time, and in certain cases, also include vacation rental homes. Our RV communities are designed to offer affordable vacation opportunities to individuals and families, complemented by a diverse selection of high-quality amenities such as restaurants, golf courses, swimming pools, and tennis courts. We operate the majority of our RV communities under the "Sun Outdoors" brand, which we believe supports our competitive advantage in the outdoor market. Sun Outdoors offers RV sites, vacation rentals, and tent camping with world-class amenities, primarily in the U.S.

Renters at our MH and RV communities lease the site on which a manufactured home, RV, or vacation rental home is located. We typically own the underlying land, utility connections, streets, lighting, driveways, common area amenities, and other capital improvements, and are responsible for enforcement of community guidelines and maintenance. In certain MH and RV communities, we do not own all of the underlying land and operate the communities pursuant to contractual ground lease arrangements. Certain communities provide water and sewer service through public or private utility companies, while other communities provide these services to residents from on-site facilities. Each owner of a home within our properties is responsible for the maintenance of the home and leased site. As a result, our capital expenditure needs are less significant relative to multi-family rental apartment complexes.

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We compete with other MH and RV communities and alternative forms of housing (such as on-site constructed homes, apartments, condominiums, and townhouses) as they provide housing alternatives to potential tenants of MH and RV communities.

UK Segment

In the UK, homeowners occupy a pitch at one of our properties through a site fee license arrangement. In addition, we sell new and pre-owned homes to current and prospective customers. We also provide vacation opportunities to individuals and families complemented by high-quality amenities. The holiday park industry in the UK is highly fragmented.

PROPERTY MANAGEMENT

Our property management strategy emphasizes intensive, detail-oriented, hands-on management by dedicated, on-site MH, RV, and UK community managers. We believe our focus on creating an exceptional resident, guest, and member experience creates a competitive advantage. It enables us to continually monitor and address concerns, the performance of competitive properties, and local market conditions. As of December 31, 2025, of our 3,614 employees, 849 were located on-site as property managers, and of those, 99.8% were full-time employees. We also selectively utilize third-party managers to oversee the operations at certain of our RV properties to further enhance the efficiency of our property management strategy. As of December 31, 2025, approximately 56 of our RV properties, or approximately 34% of our total RV properties, were managed by third-party managers.

Our MH and RV property managers in the U.S. and Canada are overseen by our Chief Operating Officer ("COO"), and a team of Senior Vice Presidents, Divisional Vice Presidents, and Regional Vice Presidents. Each Regional Vice President typically oversees seven to 17 properties and is responsible for regular property inspections, oversight of property operations and sales functions, semi-annual market surveys of competitive communities, and interaction with local manufactured home dealers. Each property manager performs regular inspections in order to monitor the physical condition of properties and to effectively address tenant concerns. In addition to an on-site manager, each district or property has on-site maintenance personnel and management support staff. We hold mandatory training sessions for all new property management personnel to ensure that policies and procedures are executed effectively and professionally. All of our property management personnel participate in on-going training to ensure that changes to policies and procedures are implemented consistently. Our internal training program has led to increased knowledge and accountability for daily operations and policies and procedures.

Our UK business is overseen by the Chief Executive Officer ("CEO") of Park Holidays, a COO, and two Regional Operations Directors who are responsible for all on-site operations in the UK.

HOME SALES AND RENTALS

We market, sell, and lease new and pre-owned homes to current and future residents in our MH and RV communities through SHS in the U.S., and to current and future holiday homeowners through our subsidiaries in the UK. Because tenants and holiday homeowners often purchase a home already on-site within a community, the services SHS and our UK subsidiaries provide enhance occupancy and property performance. Additionally, because many of the homes on the properties are sold through SHS and Park Holidays, better control of home quality in our communities can be maintained than if sales services were conducted solely through third-party brokers.

SHS also leases homes to prospective tenants. As of December 31, 2025, SHS's portfolio consists of over 12,510 occupied leased homes. New and pre-owned homes are purchased for our Rental Program. Leases associated with our Rental Program generally have a term of one year. The Rental Program requires management of costs associated with repair and refurbishment of these homes as the tenants vacate and the homes are re-leased. In 2025, we received over 33,700 applications to live in our MH and RV properties, providing a significant "resident onboarding" system that allows us to market the purchase of a home to qualified applicants. Through our Rental Program, we demonstrate our product and lifestyle to the renters, while monitoring their payment history and converting qualified renters to owners.

Park Holidays also rents homes for short-stays to allow people to experience the community park and facilities. Their short-stay experiences may, in turn, lead guests to ultimately purchase a home in a Park Holidays community. Holiday makers drive the pipeline for future home sales opportunities.

Our home sales and leasing operations compete with other national and local MH dealers, and MH community owners in the U.S., and other holiday park owners in the UK.

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SITE LEASES OR USAGE RIGHTS

Typical tenant leases for MH sites in the U.S. are year-to-year or month-to-month, renewable upon the consent of both parties, or, in some instances, as provided by statute. Certain of our leases, mainly at our Florida and California properties, are tied to the consumer price index or other indices as they relate to rent increases. Generally, market rate adjustments are made on an annual basis. These leases are cancellable for non-payment of rent, violation of community rules and regulations, or other specified defaults. During the five calendar years ended December 31, 2025, on average, less than 1.0% of the homes in our MH communities have been removed by their owners and 5.3% of the homes have been sold by their owners to a new owner who then assumes rental obligations as a community resident.

Site licenses for MH sites in the UK are for a term of 20, 30, or 40 years depending on the product originally purchased. The holiday homeowner must pay an annual site fee for their holiday home to remain on the property.

Typical resident agreements for RV sites are year-to-year or from move-in date until the end of the current calendar year. Generally, increases and market rate adjustments are made on an annual basis. These agreements are cancellable for non-payment of rent, violation of community rules and regulations, or other specified defaults.

ACQUISITION AND DISPOSITION STRATEGY

From 2010 through 2022, a large component of our growth was driven by acquisitions as we opportunistically purchased high-quality MH, RV, and UK properties. Beginning in 2023, we shifted our strategy toward optimizing the value of our business through achieving strong rental rate growth and operating efficiencies, while still pursuing select new acquisition and expansion opportunities that meet our capital investment criteria. In 2025, the Safe Harbor Sale advanced our strategy of focusing on our core business and enhanced our leverage profile and financial flexibility. We believe we are positioned for organic growth while also selectively pursuing MH and RV acquisition opportunities.

During the year ended December 31, 2025, we acquired 11 MH and three RV properties for total cash consideration of $457.0 million. During this period, we also sold four MH properties, three RV properties, and three development land parcels for a gross sale price of $202.6 million.

REGULATIONS AND INSURANCE

General

MH, RV, and UK properties are subject to various laws, ordinances, and regulations, including regulations relating to recreational facilities such as swimming pools, clubhouses, and other common areas. Each property has the necessary operating permits and approvals.

Insurance

With increased insurance claims across the industry and other challenging insurance industry-related market conditions, it has been more difficult and expensive to obtain insurance, in particular property insurance covering wind events, named windstorms, business interruption, floods, and earthquakes. With fewer insurers willing to provide policies, and policies increasingly including lower coverage limits, higher deductibles, and higher premiums, we have changed, and will continue to assess and adjust, as appropriate, our insurance coverage strategy. This has resulted in increased self-insurance exposure retained by the Company. We believe that the properties are covered by adequate comprehensive liability, fire, property, business interruption, general liability, and (where appropriate) flood, wind, and earthquake insurance through a combination of self-insurance and insurance provided by third-party providers with commercially reasonable coverage, including deductibles and limits. We maintain a blanket policy that covers all of our properties. We have obtained title insurance insuring fee title to the properties in an aggregate amount which we believe to be adequate. Claims made to our insurance carriers that are determined to be recoverable are classified in other receivables as incurred.

HUMAN CAPITAL MATTERS

Human capital management is key to our success, and focuses on employee retention and talent development practices. We are committed to building a culture that inspires and supports the growth of our employees, serves our communities, and shapes a more competitive business.

We expect our leaders to be role models and lead in a way that enables our organization to achieve success. Our strategy is anchored in promoting the right internal talent and hiring the right external talent for career opportunities across our organization. We are focused on hiring and developing talent that mirrors the markets we serve, and investing in learning opportunities and capabilities that equip our workforce with the skills they need while improving engagement and retention.

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We believe we are a stronger organization when our workforce represents a broad range of ideas and experiences. As of December 31, 2025, 50% of our employees were female, 25% of our employees (excluding those in Canada and the UK) were racially or ethnically diverse, and 47% of our employees were aged 50 years and older, with approximately 26% being aged 60 years and older.

Training and Resources

We offer training and resources on cybersecurity; fair housing and anti-discrimination laws and regulation; preventing harassment, sexual harassment, and discrimination; and leadership development. We are committed to providing a total compensation package that is market-based, performance driven, fair, and internally equitable. We conduct ongoing pay equity analyses to ensure that our employees are compensated fairly. Our goal is to be competitive both within the general employment market as well as with our competitors in the real estate industry.

Our Code of Conduct and Business Ethics is grounded in our commitment to do the right thing. It serves as the foundation of our approach to ethics and compliance. Our anti-corruption compliance program is focused on conducting business in a fair, ethical, and legal manner. We do not tolerate harassing, discriminatory, or retaliatory conduct, as such conduct is inconsistent with our policies, practices, and philosophy.

We actively seek opportunities to minimize health, safety, and environmental risks to our team members, residents, and customers we serve in our communities by utilizing safe operating procedures in compliance with safety and health laws, providing ongoing role appropriate training, conducting regular inspections and reviews, and providing the appropriate tools and safeguards for accident prevention and risk management.

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CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS

This Annual Report on Form 10-K contains various "forward-looking statements" within the meaning of the Securities Act of 1933, as amended (the "Securities Act"), and the Securities Exchange Act of 1934, as amended (the "Exchange Act"), and we intend that such forward-looking statements will be subject to the safe harbors created thereby. For this purpose, any statements contained in this document that relate to expectations, beliefs, projections, future plans and strategies, trends, or prospective events or developments, and similar expressions concerning matters that are not historical facts are deemed to be forward-looking statements. Words such as "forecasts," "intend," "goal," "estimate," "expect," "project," "projections," "plans," "predicts," "potential," "seeks," "anticipates," "should," "could," "may," "will," "designed to," "foreseeable future," "believe," "scheduled," "guidance," "target," and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these words. These forward-looking statements reflect our current views with respect to future events and financial performance, but involve known and unknown risks, uncertainties, and other factors, both general and specific to the matters discussed in this document, some of which are beyond our control. These risks, uncertainties, and other factors may cause our actual results to be materially different from any future results expressed or implied by such forward-looking statements. In addition to the risks disclosed under "Risk Factors" in this Annual Report on Form 10-K, and in our other filings with the SEC, from time to time, such risks, uncertainties and other factors include, but are not limited to:

•Our liquidity and refinancing demands;

•Our ability to obtain or refinance maturing debt;

•Our ability to maintain compliance with covenants contained in our debt facilities and our unsecured notes;

•Availability of capital;

•General volatility of the capital markets and the market price of shares of our capital stock;

•Increases in interest rates and operating costs, including insurance premiums, real estate taxes, and utilities;

•Difficulties in our ability to evaluate, finance, complete, and integrate acquisitions, developments, and expansions successfully;

•Competitive market forces;

•The ability of purchasers of manufactured homes to obtain financing;

•The level of repossessions of manufactured homes;

•Our ability to maintain effective internal control over financial reporting and disclosure controls and procedures;

•Expectations regarding the amount or frequency of impairment losses;

•Changes in general economic conditions, including inflation, deflation, energy costs, the real estate industry, the effects of tariffs or threats of tariffs, wars or other international conflicts, trade wars, immigration issues, supply chain disruptions, and the markets within which we operate;

•Changes in foreign currency exchange rates, including between the U.S. dollar and each of the British pound sterling, Canadian dollar, and Australian dollar;

•Our ability to maintain our status as a REIT;

•Changes in real estate and zoning laws and regulations;

•Our ability to maintain rental rates and occupancy levels;

•Legislative or regulatory changes, including changes to laws governing the taxation of REITs;

•Outbreaks of disease and related restrictions on business operations;

•Risks related to natural disasters such as hurricanes, earthquakes, floods, droughts, and wildfires; and

•Litigation, judgments or settlements, including costs associated with prosecuting or defending claims and any adverse outcomes.

Readers are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date the statement was made. We undertake no obligation to publicly update or revise any forward-looking statements included or incorporated by reference into this document, whether as a result of new information, future events, changes in our expectations or otherwise, except as required by law.

Although we believe that the expectations reflected in the forward-looking statements are reasonable, we cannot guarantee future results, levels of activity, performance, or achievements. All written and oral forward-looking statements attributable to us or persons acting on our behalf are qualified in their entirety by these cautionary statements.

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