Growth equity firm for bootstrapped software and healthcare services companies
M33 Growth
- HeadquartersBoston, MA S1
- Websitem33growth.com
- Last verifiedOctober 22, 2026
At a glance
| Latest fund | M33 Growth Fund III, $340M (December 2022) S6 |
|---|---|
| Revenue range | $5M+ S2 |
| Check size | $10M to $40M S2 |
| Deal types | Growth, Minority, Platform, Add-on S4 |
| Geography | United States, Canada S2 |
| Sectors | Software & SaaS, Healthcare Services |
What M33 Growth buys
M33 Growth is a Boston growth equity firm that backs founder-owned companies that have grown without much outside money. In software, it wants vertical B2B or tech-enabled services companies in the US or Canada, outside Silicon Valley, with at least $5 million of annual recurring revenue, a profit, organic growth of 20% or more, gross retention above 90% and less than $10 million of institutional money raised. In healthcare, it wants US providers with $15 million or more of revenue or $2 million or more of EBITDA, also growing about 20% a year.
It invests $10 million to $40 million per company, can hold a majority or a minority stake, and will buy shares from owners as well as fund the business. The portfolio is small on purpose: the firm says its next deal will be only its 19th as lead investor. Its third fund closed at $340 million in December 2022. M33 also helps its companies buy smaller ones, so a small business could meet it as a tuck-in.
Recent deals
Announced in the 24 months before October 22, 2026.
| Date | Company | Type | Sector | Source |
|---|---|---|---|---|
| Jan 2026 | U.S. Neurology AssociatesPartnership with a community neurology services group based in Sherman, Texas | Investment | Healthcare Services | Source |
| Aug 2025 | RosnetBack-of-house software for multi-unit restaurant operators, in business since 1998 | Growth | Software & SaaS | Source |
| Feb 2025 | Pediatrica Health GroupPartnership with a pediatric primary care provider based in Miami | Investment | Healthcare Services | Source |
| Jan 2025 | SwiftComplyCompliance management software for water utilities | Growth | Software & SaaS | Source |
| Nov 2024 | Total SynergyProject management software for architecture and engineering firms, backed jointly with PSG; a new CEO joined at closing | Growth | Software & SaaS | Source |
Portfolio by sector
From the firm's portfolio page S3.
Healthcare
- Luke
- Pediatrica Health Group
- U.S. Neurology Associates
Vertical Software
- Apogee Interactive
- BeSmartee
- BFC Software
- Clear Demand
- GoDocs
- Leading2Lean
- O3 Solutions
- Operix
- PerformLine
- Rosnet
- SmartKargo
- Swift Comply
- Thanx
- Total Synergy
Vertical Software & Healthcare
- YAPI
Past investments: Assuricare, Contruent, Mize, The Oncology Institute of Hope & Innovation, reebee, Titan Cloud, W Energy Software
Greymont’s take
How M33 Growth fits a seller
M33 suits a founder who has built a profitable software or healthcare services business without venture money and wants a partner without handing over the whole company. Its deals can let an owner sell part of their shares and keep a stake in the upside, and the firm says it works the same way as a majority or a minority owner. With a small portfolio, each company gets real attention from the partners. Rosnet and Total Synergy, both backed in the last two years, had each operated for more than 25 years.
Total Synergy also brought in a new CEO at closing, so a founder should ask early whether M33 expects to change the leadership team and how large a stake it wants. Past exits include a sale to Syncron and recapitalizations led by Riverside, Charlesbank and True Wind Capital, so it is worth asking how long M33 usually holds a company and who the likely next owner is.
Questions owners ask
What size of company does M33 Growth look for?
For software, it wants at least $5 million of annual recurring revenue, a profit and 20% or more organic growth. For healthcare services, it asks for $15 million or more of revenue or at least $2 million of EBITDA. Its checks run from $10 million to $40 million.
Will M33 Growth back a company that already raised venture capital?
Only lightly funded ones. Its software criteria call for companies that were bootstrapped or raised less than $10 million of institutional capital, and its healthcare criteria ask for bootstrapped businesses. It also says it looks for companies based outside Silicon Valley.
Can an owner take money off the table in an M33 deal?
Yes. Its target deals include secondary capital, meaning M33 buys some shares from existing owners as well as funding the company. The firm says it can be a majority or a minority investor.
Does M33 Growth invest in healthcare providers?
Yes. Current healthcare holdings include Pediatrica Health Group, a pediatric primary care provider in Miami, and U.S. Neurology Associates, a community neurology group in Sherman, Texas, whose partnership with M33 was announced in January 2026.
Sources
- S1M33 Growth home page Accessed October 22, 2026
- S2M33 Growth: Strike Zone (investment criteria) Accessed October 22, 2026
- S3M33 Growth: Companies Accessed October 22, 2026
- S4M33 Growth: Why Take Capital Accessed October 22, 2026
- S5M33 Growth: #19 Accessed October 22, 2026
- S6M33 Growth Closes $340 Million Third Fund (January 3, 2023) Accessed October 22, 2026
- S7Rosnet Secures Strategic Investment from M33 Growth (August 12, 2025) Accessed October 22, 2026
- S8Total Synergy Secures Strategic Investment from M33 Growth & PSG (November 14, 2024) Accessed October 22, 2026
- S9M33 Growth: Healthcare Accessed October 22, 2026
Compiled by Greymont Advisors from public sources, including the firm’s own website and press releases. Greymont is not affiliated with M33 Growth. Figures are as reported on the dates shown and may have changed. Request a correction