CrustdataGet an API key

YC companies in Boston

117 Y Combinator companies based in Boston, with team size, growth, open roles and funding.

Updated weekly, last on November 9, 2026. Roster from Y Combinator's public directory.

Hiring the mostlast 60 days
13 roles
TetraScienceS15
  1. 2Modern Health5
  2. 3Topline Pro5
See all 12
Fastest growingteam, 6 months
+167%
UltrasoniumS26
  1. 2Apollo Atomics, Inc.+117%
  2. 3Nextera Robotics | DIDGE.ai+29%
See all 21
Shrinkingteam, 12 months
−59%
Perceptive TechnologiesW20
  1. 2Ginkgo Bioworks−24%
  2. 3Raptor Maps−14%
See all 10
Raised the mostlast 12 months
$15M
TetraScienceS15
  1. 2Vector$10M
  2. 3Apollo Atomics, Inc.$620K
See all 3
Companies
117
Active
71
Hiring, last 60 days
12
Open roles, 60 days
40
People on these teams
4,267
Showing 50 of 117 companies
CompanyBatchTeam6 mo12 moOpen rolesTotal raisedLast round
A mental health benefits platform for employers.
W18920+2%−1%5$167MSeries D$74M, Feb 2021
Our mission is to make biology easier to engineer.
S14Public487−7%−24%1$1.6BGrant$775M, Apr 2024
The only R&D data cloud for life sciences
S15227+6%+32%13$114MUndisclosed round$15M, Feb 2026
The AI negotiation agent to help you save money on SaaS.
S19Acquired192−10%−13%0$216MSeries B$150M, Jun 2022
Generative AI powered Shopify for home service professionals
W21168+7%+27%5$44MSeries B$27M, Aug 2025
Instant, no fee international remittances.
W12Acquired123−2%−4%0
Easiest way for companies to process data requests from governments
S2199+22%+62%5$41.2MSeries A$21.2M, Sep 2025
Raptor Maps builds software to manage the solar PV lifecycle.
S1696−14%−14%1$62.2MSeries C$35M, Dec 2024
Advertising for the new internet
W2393+3%+19%YC$10MSeries A$10M, May 2026
At-Home health monitoring with silicon photonic chips for data centers
S2081+11%+31%1$32.8MSeries A$17M, Mar 2025
We Create Superior Data By Making Annotation Competitive
W1981+5%+9%YC$35.4MSeries B$16.2M, Oct 2024
Blood Test for Early Detection of Ovarian Cancer
S2156+2%+2%0$24.5MGrant$17M, May 2026
EOR for the staffing industry
W19Acquired51+9%+6%0SeedMar 2019
Unlocking the utility of genomics for the world.
W1950−4% 1$32.7MUndisclosed round$12.7M, Jan 2024
Multimodal AI Platform for Modality Agnostic Drug Discovery™
W1950−2%−6%0$26.6MUndisclosed round$550K, Oct 2024
Medicinal Chemistry powered by Machine Learning
W2041−5%−9%1$26.4MGrant$24M, May 2022
Enterprise-Grade OpenTelemetry
W2335 +21%0$13.5MSeries A$13M, Sep 2024
A national network of microschools bringing school choice to every…
S2134 −11%YC$1.6MSeed$1.5M, Jan 2024
Data integration & insights for state and local governments
W1734+21%+26%3$3.2MSeed$3.1M, Jan 2018
Agents for Accelerated Clinical Trial Design
W2532+7%+19%0$500KYC investment$500K, May 2025
We make injections as easy as pushing a button!
S2131+15%+29%YC
Non-profit building open-source voting machines for US elections.
W1931+19%+29%0SeedMar 2019
Discovering bispecific antibody drug-conjugates (BsADC) against cancer
W2130−3%+7%0$11.9MSeed$11.8M, Oct 2025
The AI Support Agent for Ecommerce
W2328−18%+22%0$5MSeed$5M, Oct 2024
We use AI to design antibodies for intractable diseases
S2028+22%+40%1$37.4MSeries A$26M, May 2024
AI-native Robotics
S2027+29%+35%YCCorporate roundAug 2026
Population health analytics powered by wastewater.
W1826−7%−4%0$41.4MSeries A$13.4M, Jun 2025
The No Infrastructure Platform as a Service
S14Acquired24 −14%0$12.1MSeries A$12M, Jun 2019
Helping low-income Americans overcome debt and rebuild credit at…
W1923−4%−4%YC$4.5MGrant$4.2M, Sep 2024
Neural interfaces to understand and use nerve data in medicine.
W1723−8%−8%0$46.8MUndisclosed round$20M, Jan 2024
Kernal is creating mRNA 2.0 therapies that work in specific cells
S2021+5%+40%3$73MGrant$48M, Oct 2025
Electricity price forecasts for energy storage, ev charging, etc.
W21Acquired17−6%−6%0$1.7MEquity crowdfunding$57K, May 2022
Metal manufacturing, faster, cheaper, and more versatile.
S2616+167% 0
Plaid for Commercial Real Estate
W2315+15%+36%0$3.3MSeed$3.3M, Oct 2023
Patent-pending enzymes to break down common dietary triggers
S2115+15%+36%0$1.6MSeed$1.5M, Oct 2021
Next-generation mRNA platform to solve cancer, COVID and climate.
W17150%−12%0$60MSeries A$231K, Apr 2024
Create custom NLP models
S2214+27%+8%0$3.5MSeed$3M, Mar 2023
We make the most compact nuclear reactors
X2613+117% 0$32.1MUndisclosed round$620K, Sep 2026
Live intelligence for biopharma teams.
S2313+18%+86%YC$3.6MSeed$3.1M, Apr 2025
Automated tooth cutting for dentists using imaging, AI and robotics
W2013−7%−59%0$20.3MUndisclosed round$15M, Jul 2025
A nonprofit stool bank enabling access to fecal transplants.
W2013−7%+8%0$100KGrant$100K, Jan 2022
Next-Generation Surgical Navigation and Robotics
S19120%0%0$13.9MSeries A$5M, Jan 2025
Personal gaming coach for PC gamers globally
S21Inactive110%0%0$3.1MYC investment$125K, Aug 2021
coaching agents for athletes
F24100%−9%0
Financial Platform for Migrant Families in America
S219  0$200KYC investment$200K, Jun 2021
Data platform for metagenomics and the microbiome.
S14Acquired90%0%0$120KUndisclosed round$120K, Jan 2017
XGenomes is building the sequencing technology of the future.
W198−20%−20%0$200KGrant$200K, Sep 2019
Robots for the inspection and maintenance of data centers
X257  0$500KYC investment$500K, Jun 2025
Gen-AI Designed Enzymes for Pharmaceutical Innovation
W237+17%+17%0$500KYC investment$500K, Apr 2023
Recover failed subscription payments to increase retention and LTV
S227−12%−12%0SeedOct 2023

How this works

1. The roster

Every launched company in YC's public directory, with its batch, status, industry and location. New companies show up the week YC lists them.

2. The numbers

Each company is matched to Crustdata by its website. Crustdata adds team size and its change over 6 and 12 months, open roles from job postings, reported funding, and founders' past employers.

3. The lists

Hiring the most counts distinct roles posted in the last 60 days. Growth needs 10+ people today, shrinking 20+ a year ago, so tiny teams do not top the lists. Rebuilt every week.

Built with Crustdata. Get your own API key and build your own.

The numbers on this page come from three Crustdata API calls. Crustdata tags 5,000+ companies with Y Combinator as an investor; swap the filter for any investor, industry or headcount range and track your own list, with founders' work emails one call away.

  • Company search for team size, growth and funding
  • Job search with a count by company, for who is hiring and for what
  • A watch that re-runs the search weekly and sends only what changed
# 1. every company with Y Combinator as an investor
curl https://api.crustdata.com/company/search \
  -H "authorization: Bearer $CRUSTDATA_API_KEY" \
  -H "x-api-version: 2025-11-01" \
  -d '{
    "filters": { "field": "funding.investors",
                 "type": "in", "value": ["Y Combinator"] },
    "fields": ["basic_info.name",
      "headcount.total", "headcount.growth_percent",
      "funding.total_investment_usd"],
    "limit": 100
  }'

# 2. open listings per company, last 60 days (limit 0 = counts only)
curl https://api.crustdata.com/job/search \
  -H "authorization: Bearer $CRUSTDATA_API_KEY" \
  -H "x-api-version: 2025-11-01" \
  -d '{
  "filters": { "op": "and", "conditions": [
    { "field": "company.basic_info.company_id",
      "type": "in", "value": [...] },
    { "field": "metadata.date_added",
      "type": "=>", "value": "2026-08-24" } ]},
  "limit": 0,
  "aggregations": [{ "type": "group_by",
    "field": "company.basic_info.company_id", "agg": "count" }]
}'

# 3. the same company filter as a weekly watch: POST /watch/company/search

Questions about Boston YC companies

How many Boston YC companies are there?

117 Y Combinator companies are based in Boston; 71 are active.

Which Boston YC companies are hiring?

12 companies posted roles in the last 60 days, led by TetraScience (13 roles), Modern Health (5 roles) and Topline Pro (5 roles). 19 mark themselves as hiring on YC's directory.

Which Boston YC companies are growing fastest?

By team growth over 6 months (10+ people): Ultrasonium (+167%), Apollo Atomics, Inc. (+117%) and Nextera Robotics | DIDGE.ai (+29%).

Which Boston YC companies raised the most?

Largest latest rounds in the last 12 months, after their YC batch: TetraScience ($15M), Vector ($10M) and Apollo Atomics, Inc. ($620K).

Browse YC companies

By batch

Show fewer

By industry

Show fewer

By location

Show fewer

By founders' past employer

Show fewer