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.
| Company | Batch | Team | 6 mo | 12 mo | Open roles | Total raised | Last round |
|---|---|---|---|---|---|---|---|
Building the world's first fusion power plant | S14 | 594 | +11% | +34% | 49 | $1.5B | Series G$500M, Jun 2026 |
Seamless mobility to, through, and from space. It starts with 100%… | W21 | 451 | +17% | +33% | 4 | $2.4B | Series E$1B, Sep 2026 |
Mason is the fastest way to take smart devices from idea to end user | W16 | 251 | +2% | +2% | YC | $25.1M | Undisclosed round$25M, Dec 2020 |
Captures user interactions with no code to generate analytics. | W13Acquired | 98 | −5% | −15% | 0 | $218M | Series D$110M, Dec 2021 |
We empower the world’s hiring teams to grow engaged, high-performing… | W20 | 86 | +12% | +19% | 2 | $55.2M | Series B$25M, Apr 2026 |
Home Inspections, Simplified | S20 | 82 | +1% | +4% | 2 | $22.5M | Undisclosed round$5.3M, Oct 2024 |
Automating non-emergency calls for 911 centers | S22 | 69 | +30% | +123% | 6 | $14.5M | Series A$14M, Aug 2025 |
Data centers in space | S24 | 66 | +57% | +128% | YC | $444M | Series A$250M, Aug 2026 |
We help companies scale marketing campaigns through WhatsApp | S19 | 66 | +8% | +2% | 0 | $15M | Series A$15M, Jul 2022 |
24/7 emergency maintenance department for property managers and… | W19 | 64 | −3% | −2% | 0 | $24.3M | Undisclosed round$16.7M, Mar 2023 |
We make beautiful connected light switches that allow you to control… | W16 | 64 | +7% | −2% | 1 | $22.2M | Series B$12.5M, Mar 2021 |
AI agent that saves you money on travel | W19 | 48 | +71% | +200% | 1 | ||
Investment management platform for real estate | W22 | 42 | +11% | +11% | 0 | $4.5M | Seed (before YC)$3.5M, Nov 2021 |
AI Scribe for veterinarians. Saving time and improving patient care. | S23 | 28 | −24% | +22% | 0 | $500K | YC investment$500K, Sep 2023 |
Automate security and privacy reviews | S24 | 25 | +47% | +67% | 2 | $13.4M | Seed$8.4M, Feb 2026 |
Discovering drugs that target the DNA regulome | S21 | 24 | −8% | −8% | 0 | $27.8M | Seed$11.2M, Sep 2026 |
Game that teaches computer science to middle and high school kids. | W14 | 24 | −14% | −14% | 0 | $9.1M | Undisclosed round$326K, May 2023 |
Stripe-like API Docs in just a few clicks | W22 | 23 | +15% | +10% | 0 | $532K | Undisclosed round$500K, Nov 2023 |
Booktrope provides a software platform that makes it easy for… | W15Inactive | 23 | 0% | 0% | 0 | $2.3M | Angel$1.2M, Apr 2015 |
Building the first sensor enabled marketplace for repeat purchases | W19 | 20 | +5% | +11% | 0 | $6.8M | Series A$4.5M, Jan 2021 |
AI platform for phone-first sellers | W24 | 18 | +20% | +100% | YC | $500K | Seed$500K, Jan 2026 |
Rebellyous Foods is a food manufacturing technology and production… | S18 | 18 | +13% | +6% | 0 | $43.5M | Series B$2.4M, Jan 2025 |
Develop your CI/CD pipelines as code and run them anywhere | W19 | 15 | 0% | −6% | 0 | $30M | Series A$20M, Mar 2022 |
Transforms how grocery stores buy highly perishable foods. | S18Acquired | 15 | −6% | 0 | $58.2M | Series B$41M, Mar 2021 | |
Analytics to improve how teams work and collaborate | W18 | 15 | +7% | +7% | 0 | SeedJan 2018 | |
Poppy makes it easy for parents to find high quality childcare with… | W16Inactive | 15 | 0% | 0% | 0 | $120K | YC investment$120K, Mar 2016 |
Voice AI | S22 | 14 | +75% | +27% | 0 | ||
Building persistent, high-performance infrastructure in the sky | W23 | 13 | +18% | 0 | $5M | Seed$4.5M, Jan 2024 | |
We design and manufacture energy efficient LED lighting fixtures for… | S15 | 13 | +8% | 0 | $3.1M | Undisclosed round$2M, Apr 2018 | |
Data Discovery, DLP, DSPM for SaaS, Cloud, Gen AI & Endpoints | W22 | 12 | 1 | $4M | Seed$3.5M, Jul 2022 | ||
Foundation models to simulate Earth, starting with weather. | S24 | 11 | −15% | −15% | YC | $500K | YC investment$500K, Sep 2024 |
Code-first scrapers and RPAs, built and maintained by AI | S22 | 11 | −15% | −15% | 0 | $500K | YC investment$500K, Aug 2022 |
The first test designed to prevent birth control side effects | S20 | 10 | +25% | +43% | YC | $2.6M | Seed$2.5M, Apr 2021 |
Dollar Shave Club as a platform. | S20 | 9 | 0% | 0% | 0 | Undisclosed roundJan 2023 | |
The Family AI - a copilot for parents to tackle the invisible load of… | W20Inactive | 9 | 0% | −18% | 0 | SeedAug 2023 | |
The programming language for AI | W23 | 8 | −33% | YC | SeedJan 2025 | ||
Take Back Control of your Time | W08 | 8 | −11% | −11% | 0 | $920K | Series A$900K, Sep 2008 |
AI operating system for mega-scale satellite networks. | W26 | 7 | 2 | $6.5M | Grant$6.5M, Apr 2026 | ||
Changing divorce for good by making it a way less horrible experience… | W13 | 7 | 0% | 0% | 0 | $6.5M | Undisclosed round$3.1M, Jul 2016 |
The AIOps Agent for ML Teams | W26 | 6 | 0 | $500K | YC investment$500K, Mar 2026 | ||
AI for Post-Acute Senior Care (Hospice, Home Health, Skilled Nursing… | F24 | 6 | +20% | +20% | YC | ||
Sigma Genetics is a biotechnology company that is building… | W17 | 6 | 0 | Non-equity supportMar 2026 | |||
A Roomba for weeds on a farm. | W25 | 5 | 0 | $500K | YC investment$500K, Mar 2025 | ||
Remix any song into any style | W24Inactive | 4 | −20% | −33% | 0 | $500K | YC investment$500K, Feb 2024 |
Building your AI coworkers for any team, workflow, or industry. | W23 | 4 | 0 | $500K | YC investment$500K, Apr 2023 | ||
Real-time generative AI | W23 | 4 | 0 | $500K | YC investment$500K, Apr 2023 | ||
create and share mini-apps with friends | S21 | 4 | YC | Pre-seedJun 2021 | |||
Makers of simple, affordable medical devices. Our award-winning… | W15Acquired | 4 | 0 | $1.2M | Seed$1.2M, Jul 2015 | ||
AI for Commercial Insurance Agencies | W25 | 3 | −40% | −40% | 0 | $1.9M | Seed$1.8M, Apr 2025 |
AI for public records request fulfillment | S24 | 3 | 0 | $500K | YC investment$500K, Sep 2024 |
Every launched company in YC's public directory, with its batch, status, industry and location. New companies show up the week YC lists them.
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.
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.
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.
# 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
86 Y Combinator companies are based in Seattle; 54 are active.
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.
By team growth over 6 months (10+ people): Feather (+75%), Axel Travel (+71%) and Starcloud (+57%).
Largest latest rounds in the last 12 months, after their YC batch: Stoke Space ($1B), Helion Energy ($500M) and Starcloud ($250M).