Growth equity firm

Mainsail Partners

At a glance

Latest fundMainsail Partners VII, $1.5B (May 2025) S4
Check size$25M to $200M S2
Deal typesGrowth, Add-on S2
GeographyUnited States, Canada S2
SectorsSoftware & SaaS, Cybersecurity

What Mainsail Partners buys

Mainsail Partners is a growth equity firm with offices in Austin and San Francisco that has backed bootstrapped, founder-owned B2B software companies since 2003. Its criteria call for founder ownership, recurring revenue, high gross margins and customer retention, rapid growth, and a base in the US or Canada, with equity investments of $25 million to $200 million. Most of its 29 current companies make software for a single trade or profession, such as pool service, chiropractic, fire inspection, heavy equipment dealers, metal finishing shops, property managers and movers. It also looks at fintech, vertical AI and tech-enabled services.

Mainsail typically backs companies that have never taken outside capital, and the checks are large: $84 million for Steelhead Technologies and $54 million for CourtReserve in late 2025. It closed its seventh fund at $1.535 billion in May 2025. Smaller software businesses mostly meet Mainsail as add-ons, such as Pool Builder Geek and Poologics joining Skimmer in August 2026 or ChiroBilling joining ChiroHD in October 2026.

Recent deals

Announced in the 24 months before October 29, 2026.

DateCompanyTypeSectorSource
Oct 2026Providi (Cerbo and OptiMantra)Two practice management software makers for personalized care clinics, combined in 2025 with Mainsail growth capital, now operate as ProvidiInvestmentSoftware & SaaSSource
Oct 2026ChiroBillingOutsourced chiropractic billing company added to ChiroHDAdd-onSoftware & SaaSSource
Aug 2026Pool Builder Geek and PoologicsTwo pool construction software products added to Skimmer; the Pool Builder Geek founder joined Skimmer to lead construction strategyAdd-onSoftware & SaaSSource
Jul 2026Visual Shop and BluestreakJob shop management and quality software added to Steelhead TechnologiesAdd-onSoftware & SaaSSource
Jul 2026Red Oak and MirrorWebDefinitive agreement to combine two Mainsail-backed compliance software companies for financial firmsAdd-onSoftware & SaaSSource
Dec 2025Steelhead Technologies$84 million for ERP software used by metal finishing and fabrication shops; the co-founder remains CEOGrowthSoftware & SaaSSource
Oct 2025FieldFlo$35 million for project and safety software used by specialty subcontractorsGrowthSoftware & SaaSSource
Oct 2025CourtReserve$54 million for club management software used by racquet and paddle sports facilitiesGrowthSoftware & SaaSSource
Oct 2025GTreasuryHg agreed to sell the treasury software company to Ripple for $1 billion; minority holder Mainsail exits alongside itExitSoftware & SaaSSource
Oct 2025RentFinder AIRent pricing intelligence tools added to Rentvine, a property management software companyAdd-onSoftware & SaaSSource
Oct 2025Flyntlok$36 million for dealer management software used by heavy equipment dealersGrowthSoftware & SaaSSource
Sep 2025PlanHubConstruction bidding platform acquired by GrowthCurve Capital; Mainsail keeps a minority stakeExitSoftware & SaaSSource
Aug 2025Alliant Systems and Infinite LaundryMerged with Linenmaster under the new Texo brand for commercial laundry operatorsAdd-onSoftware & SaaSSource
Aug 2025Life Safety Inspection Vault (LIV)$28.7 million for fire and life safety compliance software used by fire bureaus and municipalitiesGrowthSoftware & SaaSSource
May 2025Mainsail Partners VIIClosed at its $1.535 billion hard cap, the firm's largest fundFund closeSource
Apr 2025ChiroHD$26 million for practice management software used by chiropractorsGrowthSoftware & SaaSSource
Apr 20254U PlatformContent distribution platform for the investment industry added to Red OakAdd-onSoftware & SaaSSource
Mar 2025Inn-Flow$45 million for back-office and accounting software used by hotelsGrowthSoftware & SaaSSource
Nov 2024JobNimbusSumeru Equity Partners made a $330 million growth investment in the roofing contractor software company; Mainsail and the co-founders stay investedInvestmentSoftware & SaaSSource
Nov 2024FloorzapFlooring and remodeling business software added to TeamfrontAdd-onSoftware & SaaSSource

Portfolio by sector

From the firm's portfolio page S2.

Current

  • Providi
  • Steelhead Technologies
  • FieldFlo
  • CourtReserve
  • Flyntlok
  • LIV (Life Safety Inspection Vault)
  • ChiroHD
  • Inn-Flow
  • Skimmer
  • Rentvine
  • Innergy
  • Teamfront
  • Texo (formerly Linenmaster)
  • ProShop
  • Red Oak
  • Instinct Science
  • SmartMoving
  • Fexa
  • Flight Schedule Pro
  • Apptega
  • ServiceCore
  • Inspect Point
  • Centerbase
  • Boostlingo
  • JobNimbus
  • PlanHub Active (minority since 2025)
  • Syncro
  • Fullbay
  • Brilliant Earth

Greymont’s take

How Mainsail Partners fits a seller

Mainsail fits a founder who built a niche software company without outside money and now wants capital and hands-on help to grow faster, rather than a clean, full exit. Its deals are presented as growth investments, and founder-CEOs such as Sean McLaughlin at Flyntlok and Jeff Halonen at Steelhead were still leading their companies when the investments were announced.

Mainsail tends to hold for several years and then bring in a larger investor while keeping a smaller stake. Sumeru put $330 million into JobNimbus in November 2024 and GrowthCurve bought PlanHub in September 2025, with Mainsail staying invested in both. A founder should ask whether the deal gives Mainsail majority control, how much of the money goes to the founder now versus into the company, and what a later sale to another investor would mean for the founder's remaining shares.

Questions owners ask

What kind of company does Mainsail invest in?

Founder-owned B2B software companies in the US or Canada with recurring revenue, high gross margins, high customer retention and rapid growth. It makes equity investments of $25 million to $200 million, mostly in vertical software built for one industry.

Has Mainsail raised a new fund recently?

Yes. In May 2025 it closed Mainsail Partners VII at its $1.535 billion hard cap, the largest fund in its history, bringing total commitments raised since 2003 to nearly $4 billion.

Does Mainsail sell its companies to other investors?

Often, at least in part. GrowthCurve Capital bought PlanHub in September 2025 with Mainsail staying on as a minority holder, and Sumeru Equity Partners made a $330 million investment in JobNimbus in November 2024 alongside Mainsail and the co-founders.

Does Mainsail invest in software for trades and field services?

Yes. Current holdings include Skimmer for pool service companies, ServiceCore for liquid waste and roll-off businesses, Fullbay for heavy-duty repair shops, Inspect Point for fire inspection companies and SmartMoving for movers. These are software makers, not the service companies themselves.

Sources

  1. S1Mainsail Partners home page Accessed October 29, 2026
  2. S2Mainsail Partners: Portfolio and investment criteria Accessed October 29, 2026
  3. S3Mainsail Partners: Why Mainsail Accessed October 29, 2026
  4. S4Mainsail Partners Raises $1.535 Billion Fund VII (May 7, 2025) Accessed October 29, 2026
  5. S5Mainsail Partners: News & Insights Accessed October 29, 2026
  6. S6Steelhead Technologies Announces $84M Growth Capital Investment from Mainsail Partners (December 11, 2025) Accessed October 29, 2026
  7. S7GrowthCurve Capital Acquires PlanHub (September 16, 2025) Accessed October 29, 2026
  8. S8Sumeru Equity Partners Invests $330 Million in JobNimbus (November 13, 2024) Accessed October 29, 2026
  9. S9Flyntlok Secures $36 Million Growth Investment from Mainsail Partners (October 8, 2025) Accessed October 29, 2026
  10. S10Mainsail Partners post sitemap (news post list) Accessed October 29, 2026

Compiled by Greymont Advisors from public sources, including the firm’s own website and press releases. Greymont is not affiliated with Mainsail Partners. Figures are as reported on the dates shown and may have changed. Request a correction

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