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Top Series B companies in Boston

Companies that have closed a Series B — proven scaling motion, hiring aggressively. Filtered to companies headquartered in Boston.

Built from a search like: Top Series B companies in Boston

Ranked by current headcount across Series B companies headquartered in Boston. Refreshed daily.

  1. 1
    Foundation Medicine· Boston, Massachusetts, United States
    • Series B
    • 1.8k employees
    • Founded 2010
  2. 2
    Mendix· Boston, Massachusetts, United States
    • Series B
    • 1.1k employees
    • Founded 2005
  3. 3
    Lusha· Boston, Massachusetts, United States
    • Series B
    • 366 employees
    • Founded 2016
  4. 4
    iboss· Boston, Massachusetts, United States
    • Series B
    • 360 employees
    • Founded 2003
  5. 5
    InStride Health· Boston, Massachusetts, United States
    • Series B
    • 297 employees
    • Founded 2021
  6. 6
    HYCU, Inc.· Boston, Massachusetts, United States
    • Series B
    • 251 employees
    • Founded 2018
  7. 7
    Vendr· Boston, Massachusetts, United States
    • Series B
    • 220 employees
    • Founded 2019
  8. 8
    Form Health· Boston, Massachusetts, United States
    • Series B
    • 214 employees
    • Founded 2019
  9. 9
    NetWitness· Boston, Massachusetts, United States
    • Series B
    • 189 employees
    • Founded 1997
  10. 10
    Teikametrics· Boston, Massachusetts, United States
    • Series B
    • 184 employees
    • Founded 2015
  11. 11
    Origin· Boston, Massachusetts, United States
    • Series B
    • 166 employees
    • Founded 2018
  12. 12
    NewStore· Boston, Massachusetts, United States
    • Series B
    • 165 employees
    • Founded 2015
  13. 13
    Videa· Boston, Massachusetts, United States
    • Series B
    • 165 employees
    • Founded 2018
  14. 14
    Black Kite· Boston, Massachusetts, United States
    • Series B
    • 164 employees
    • Founded 2016
  15. 15
    Posh· Boston, Massachusetts, United States
    • Series B
    • 159 employees
    • Founded 2018
  16. 16
    Hi Marley· Boston, Massachusetts, United States
    • Series B
    • 158 employees
    • Founded 2017
  17. 17
    QuEra Computing Inc.· Boston, Massachusetts, United States
    • Series B
    • 152 employees
    • Founded 2018
  18. 18
    Grip Security· Boston, Massachusetts, United States
    • Series B
    • 152 employees
    • Founded 2021
  19. 19
    Mori· Boston, Massachusetts, United States
    • Series B
    • 138 employees
    • Founded 2016
  20. 20
    CodaMetrix· Boston, Massachusetts, United States
    • Series B
    • 138 employees
    • Founded 2019
  21. 21
    Current Health· Boston, Massachusetts, United States
    • Series B
    • 137 employees
    • Founded 2015
  22. 22
    Mine· Boston, Massachusetts, United States
    • Series B
    • 135 employees
    • Founded 2019
  23. 23
    Pickle Robot Company· Boston, Massachusetts, United States
    • Series B
    • 129 employees
    • Founded 2018
  24. 24
    Empatica· Boston, Massachusetts, United States
    • Series B
    • 127 employees
    • Founded 2011
  25. 25
    IP Fabric· Boston, Massachusetts, United States
    • Series B
    • 117 employees
    • Founded 2015

Find engineers at Series B companies in Boston

Series B companies in Boston are some of the fastest-moving employers in the market. The list above ranks the largest Series B-stage companies headquartered in Boston by current headcount, drawn from public LinkedIn and Crunchbase records. With 113 matching companies in our index, the density of senior engineers, designers, and founders is unusually high.

At Series B, teams tend to be small, ambitious, and on the hunt for senior talent. The companies on this list are good signals for where the Bostontalent market is heating up — and for which engineers and founders are about to become tomorrow’s operators.

Refolk converts this list into a live search. Ask for “founders of Series B companies in Boston” or “senior engineers at Series B companies in Boston hiring” and Refolk returns a ranked shortlist with evidence behind each match.

How this list is built

Refolk pulled Series B companies headquartered in Boston from public LinkedIn and Crunchbase records, ranked them by current employee count, and kept those with at least 5 employees. The list refreshes once a day.

Last refreshed: Thu, 07 May 2026 06:43:22 GMT

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