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YC companies in Seattle

86 Y Combinator companies based in Seattle, 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
49 roles
Helion EnergyS14
  1. 2Aurelian6
  2. 3Stoke Space4
See all 10
Fastest growingteam, 6 months
+75%
FeatherS22
  1. 2Axel Travel+71%
  2. 3Starcloud+57%
See all 19
Shrinkingteam, 12 months
−14%
CodeCombatW14
  1. 2Talus Bio−8%
  2. 3Deako−2%
See all 4
Raised the mostlast 12 months
$1B
Stoke SpaceW21
  1. 2Helion Energy$500M
  2. 3Starcloud$250M
See all 7
Companies
86
Active
54
Hiring, last 60 days
10
Open roles, 60 days
70
People on these teams
2,454
Showing 50 of 86 companies
CompanyBatchTeam6 mo12 moOpen rolesTotal raisedLast round
Building the world's first fusion power plant
S14594+11%+34%49$1.5BSeries G$500M, Jun 2026
Seamless mobility to, through, and from space. It starts with 100%…
W21451+17%+33%4$2.4BSeries E$1B, Sep 2026
Mason is the fastest way to take smart devices from idea to end user
W16251+2%+2%YC$25.1MUndisclosed round$25M, Dec 2020
Captures user interactions with no code to generate analytics.
W13Acquired98−5%−15%0$218MSeries D$110M, Dec 2021
We empower the world’s hiring teams to grow engaged, high-performing…
W2086+12%+19%2$55.2MSeries B$25M, Apr 2026
Home Inspections, Simplified
S2082+1%+4%2$22.5MUndisclosed round$5.3M, Oct 2024
Automating non-emergency calls for 911 centers
S2269+30%+123%6$14.5MSeries A$14M, Aug 2025
Data centers in space
S2466+57%+128%YC$444MSeries A$250M, Aug 2026
We help companies scale marketing campaigns through WhatsApp
S1966+8%+2%0$15MSeries A$15M, Jul 2022
24/7 emergency maintenance department for property managers and…
W1964−3%−2%0$24.3MUndisclosed round$16.7M, Mar 2023
We make beautiful connected light switches that allow you to control…
W1664+7%−2%1$22.2MSeries B$12.5M, Mar 2021
AI agent that saves you money on travel
W1948+71%+200%1
Investment management platform for real estate
W2242+11%+11%0$4.5MSeed (before YC)$3.5M, Nov 2021
AI Scribe for veterinarians. Saving time and improving patient care.
S2328−24%+22%0$500KYC investment$500K, Sep 2023
Automate security and privacy reviews
S2425+47%+67%2$13.4MSeed$8.4M, Feb 2026
Discovering drugs that target the DNA regulome
S2124−8%−8%0$27.8MSeed$11.2M, Sep 2026
Game that teaches computer science to middle and high school kids.
W1424−14%−14%0$9.1MUndisclosed round$326K, May 2023
Stripe-like API Docs in just a few clicks
W2223+15%+10%0$532KUndisclosed round$500K, Nov 2023
Booktrope provides a software platform that makes it easy for…
W15Inactive230%0%0$2.3MAngel$1.2M, Apr 2015
Building the first sensor enabled marketplace for repeat purchases
W1920+5%+11%0$6.8MSeries A$4.5M, Jan 2021
AI platform for phone-first sellers
W2418+20%+100%YC$500KSeed$500K, Jan 2026
Rebellyous Foods is a food manufacturing technology and production…
S1818+13%+6%0$43.5MSeries B$2.4M, Jan 2025
Develop your CI/CD pipelines as code and run them anywhere
W19150%−6%0$30MSeries A$20M, Mar 2022
Transforms how grocery stores buy highly perishable foods.
S18Acquired15 −6%0$58.2MSeries B$41M, Mar 2021
Analytics to improve how teams work and collaborate
W1815+7%+7%0SeedJan 2018
Poppy makes it easy for parents to find high quality childcare with…
W16Inactive150%0%0$120KYC investment$120K, Mar 2016
Voice AI
S2214+75%+27%0
Building persistent, high-performance infrastructure in the sky
W2313 +18%0$5MSeed$4.5M, Jan 2024
We design and manufacture energy efficient LED lighting fixtures for…
S1513 +8%0$3.1MUndisclosed round$2M, Apr 2018
Data Discovery, DLP, DSPM for SaaS, Cloud, Gen AI & Endpoints
W2212  1$4MSeed$3.5M, Jul 2022
Foundation models to simulate Earth, starting with weather.
S2411−15%−15%YC$500KYC investment$500K, Sep 2024
Code-first scrapers and RPAs, built and maintained by AI
S2211−15%−15%0$500KYC investment$500K, Aug 2022
The first test designed to prevent birth control side effects
S2010+25%+43%YC$2.6MSeed$2.5M, Apr 2021
Dollar Shave Club as a platform.
S2090%0%0Undisclosed roundJan 2023
The Family AI - a copilot for parents to tackle the invisible load of…
W20Inactive90%−18%0SeedAug 2023
The programming language for AI
W238−33% YCSeedJan 2025
Take Back Control of your Time
W088−11%−11%0$920KSeries A$900K, Sep 2008
AI operating system for mega-scale satellite networks.
W267  2$6.5MGrant$6.5M, Apr 2026
Changing divorce for good by making it a way less horrible experience…
W1370%0%0$6.5MUndisclosed round$3.1M, Jul 2016
The AIOps Agent for ML Teams
W266  0$500KYC investment$500K, Mar 2026
AI for Post-Acute Senior Care (Hospice, Home Health, Skilled Nursing…
F246+20%+20%YC
Sigma Genetics is a biotechnology company that is building…
W176  0Non-equity supportMar 2026
A Roomba for weeds on a farm.
W255  0$500KYC investment$500K, Mar 2025
Remix any song into any style
W24Inactive4−20%−33%0$500KYC investment$500K, Feb 2024
Building your AI coworkers for any team, workflow, or industry.
W234  0$500KYC investment$500K, Apr 2023
Real-time generative AI
W234  0$500KYC investment$500K, Apr 2023
create and share mini-apps with friends
S214  YCPre-seedJun 2021
Makers of simple, affordable medical devices. Our award-winning…
W15Acquired4  0$1.2MSeed$1.2M, Jul 2015
AI for Commercial Insurance Agencies
W253−40%−40%0$1.9MSeed$1.8M, Apr 2025
AI for public records request fulfillment
S243  0$500KYC investment$500K, Sep 2024

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 Seattle YC companies

How many Seattle YC companies are there?

86 Y Combinator companies are based in Seattle; 54 are active.

Which Seattle YC companies are hiring?

10 companies posted roles in the last 60 days, led by Helion Energy (49 roles), Aurelian (6 roles) and Stoke Space (4 roles). 15 mark themselves as hiring on YC's directory.

Which Seattle YC companies are growing fastest?

By team growth over 6 months (10+ people): Feather (+75%), Axel Travel (+71%) and Starcloud (+57%).

Which Seattle YC companies raised the most?

Largest latest rounds in the last 12 months, after their YC batch: Stoke Space ($1B), Helion Energy ($500M) and Starcloud ($250M).

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