Investor Lists

Series B investors based in Boston

Updated 7 November 2026

Firms with an address in Boston that we have watched take part in a Series B round in the last two years.

See all 54 →The top 25
54investors on the listNo change this week
673cheques in 12 months+3% against the market
$34Mmedian round they joined+319% against the market median
98%wrote a cheque in 12 months
69%have led a round

The Top 25

Ordered by cheques observed, never by anything anyone paid for

Deploying now (25)

  1. 1MassChallengeDeploying nowAccelerator · United States984$1.8Mmedian roundSept 2026last seen
  2. 2Battery VenturesDeploying nowVC firm · United States658$32Mmedian roundNov 2026last seen
  3. 3Polaris PartnersDeploying nowVC firm · United States490$36Mmedian roundOct 2026last seen
  4. 4RA Capital ManagementDeploying nowPrivate equity · United States395$93Mmedian roundNov 2026last seen
  5. 5Summit PartnersDeploying nowPrivate equity · United States356$81Mmedian roundOct 2026last seen
  6. 6Wellington ManagementDeploying nowVC firm · United States297$130Mmedian roundOct 2026last seen
  7. 7Cormorant Asset ManagementDeploying nowPrivate equity · United States176$102Mmedian roundOct 2026last seen
  8. 8MPM CapitalDeploying nowPrivate equity · United States139$60Mmedian roundDec 2025last seen
  9. 9Omega FundsDeploying nowVC firm · United States104$88Mmedian roundSept 2026last seen
  10. 10Flare CapitalDeploying nowVC firm · United States93$12Mmedian roundOct 2026last seen
  11. 11HarbourVest PartnersDeploying nowFund of funds · United States93$54Mmedian roundJun 2026last seen
  12. 12MassMutual VenturesDeploying nowVC firm · United States84$14Mmedian roundOct 2026last seen
  13. 13Pillar VCDeploying nowVC firm · United States83$8.2Mmedian roundSept 2026last seen
  14. 14Castle Island VenturesDeploying nowVC firm · United States78$7Mmedian roundOct 2026last seen
  15. 15The E14 FundDeploying nowVC firm · United States72$8Mmedian roundOct 2026last seen
  16. 16One Way VenturesDeploying nowVC firm · United States71$8Mmedian roundNov 2026last seen
  17. 17PSGDeploying nowVC firm · United States68$50Mmedian roundAug 2026last seen
  18. 18Underscore VCDeploying nowVC firm · United States65$7Mmedian roundSept 2026last seen
  19. 19HubSpot VenturesDeploying nowCorporate VC · United States64$25Mmedian roundNov 2026last seen
  20. 20Four Cities CapitalDeploying nowVC firm · United States62$5.3Mmedian roundOct 2026last seen
  21. 21Advent InternationalDeploying nowPrivate equity · United States59$740Mmedian roundOct 2026last seen
  22. 22Bain CapitalDeploying nowPrivate equity · United States58$50Mmedian roundAug 2026last seen
  23. 23Spectrum EquityDeploying nowPrivate equity · United States55$62Mmedian roundSept 2026last seen
  24. 24ElephantDeploying nowVC firm · United States54$16Mmedian roundJul 2026last seen
  25. 25Longwood FundDeploying nowVC firm · United States53$60Mmedian roundAug 2026last seen
29 more on this list

All 54 are in the app, with filters for stage, sector and market. A free account shows 10 per search, Pro up to 1,000.

See the whole list →

Quick answers about series B investors based in Boston

Who are the most active series B investors based in Boston?

By cheques observed, the most active are MassChallenge, Battery Ventures, Polaris Partners, RA Capital Management and Summit Partners.

How many series B investors based in Boston are there?

54 are on record. 98% made an investment in the last 12 months and 69% have led a round.

Which stages do series B investors based in Boston back?

Of the rounds with a named stage in the last 12 months, mostly Series B (21%) and Series A (21%).

How big are the rounds series B investors based in Boston join?

The typical (median) round among the leading investors here is $36M.

Which sectors do series B investors based in Boston back most?

In the last 12 months, mostly AI, Biotech and Healthcare.

Which series B investors based in Boston lead the most rounds?

Battery Ventures (29 led), RA Capital Management (15 led) and Wellington Management (15 led).

What have series B investors based in Boston invested in recently?

Recent rounds include Alethio Therapeutics (Series A, Nov 2026, with RA Capital Management), Shackleton AI (Seed, Nov 2026, with Battery Ventures) and Lazarus AI (Nov 2026, with One Way Ventures).

How is this list of series B investors based in Boston ranked?

By cheques observed, from the rounds and filings we watched, and never by anything anyone paid for. It is rebuilt every night.

Built from the rounds we watched, refreshed every night. How we count · Report a correction