Mainsail Partners is a growth equity firm that invests in bootstrapped, founder-led B2B software and AI-enabled companies to help them scale and grow into market leaders. Founded in 2003, the firm has offices in San Francisco and Austin and has raised nearly $4 billion in committed capital across seven funds.
Deal activity decreased year-over-year (1 deal in the last 12 months vs 2 prior). Their most common stage is growth (71% of deals). Average disclosed round size is $53.1M (across 25 rounds with reported amounts).
Portfolio
24
Fund Size
$1.5B
Top Stage
Growth
Last 12 Mo
1
Team
Portfolio Breakdown
Stage Distribution
Sector Distribution
Investment Activity
DealsAvg Round Size
Portfolio
28 investments
| Company | Round | Amount | Date |
|---|---|---|---|
 FieldFlo | Growth | $35M | Oct 2025 |
| IInn-Flow | Growth | $45M | Mar 2025 |
| FFlyntlok | Growth | $36M | Jan 2025 |
| IInn-Flow | Growth | $45M | Jan 2025 |
| CCourtReserve | Growth | $54M | Jan 2025 |
| CChiroHD | Growth | $26M | Jan 2025 |
| SSkimmer | Growth | $74M | Oct 2024 |
 Jobnimbus | Growth | $330M | Jan 2024 |
| RRentvine | Growth | $74M | Jan 2024 |
| LLinenMaster | Growth | — | Nov 2023 |
| PProShop | Growth | — | Jan 2023 |
| SSmartMoving | Seed | $41.5M | Aug 2022 |
| SServiceCore | Unknown | $54M | Jan 2022 |
| FFlight Schedule Pro | Unknown | $31M | Jan 2022 |
| FFexa | Unknown | $40M | Jan 2022 |
| SSmartMoving | Growth | $41.5M | Jan 2022 |
| Jobnimbus | Unknown | $53M | Jan 2021 |
 FairWarning | Growth | $60M | Jun 2018 |
| GGTreasury | Unknown | $42M | Oct 2017 |
| SSteelwedge | Unknown | $22.5M | Jan 2017 |
| SSteelwedge | Growth | $22.5M | Jan 2015 |
 ResMan | Growth | $36M | — |
 Apptega | Growth | $37M | — |
| BBio-Optronics | Growth | $30M | — |
| NNetchemia | Growth | $6.5M | — |
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Top Co-Investors
Sumeru Equity Partners2 shared
Supply Chain Ventures2 shared
RJT Credit2 shared
Verdane1 shared
Circadian Ventures1 shared
JAFCO Group Co., Ltd.1 shared
Globespan Capital Partners1 shared
Aspex Management1 shared
Full In Partners1 shared
Maven1 shared
Last updated: 20 October 2026