Top 100 Y Combinator Companies in 2026: Biggest YC Startups and Alumni

Quick Answer: Y Combinator has backed more than 5,600 startups since 2005, including Stripe, Airbnb, DoorDash, Coinbase, Instacart, Dropbox, Reddit, and Rippling. As of 2026, YC companies have a combined estimated portfolio value of more than $600 billion. This ranking compares 100 notable Y Combinator companies based on total disclosed funding raised.

How does a three-month program turn unknown founders into billion-dollar companies? That’s the question behind Y Combinator’s more than two-decade track record. Since its first batch in the summer of 2005, YC has backed 5,668 startups, many of them pre-product, pre-revenue, and pre-team. The ones that made it didn’t just survive Demo Day; they reshaped entire industries. Together, their combined estimated portfolio valuation exceeds $600 billion as of 2026 distinct from the $145 billion in follow-on equity funding the portfolio has collectively raised.

What began as a small experiment in Mountain View, California, providing seed funding and guidance to small founding teams, has grown into a formal organization that influences how the global technology industry sources, funds, and scales early-stage startups. The YC stamp of approval sends a clear message: alumni raise more money, attract better co-investors, and benefit from a network of over 11,000 founders who actively help each other hire, sell, and fundraise.

Key Takeaways

• YC has funded 5,668 companies since 2005, with a combined estimated portfolio valuation of $600B+ and $145B+ in follow-on funding raised.
• The accelerator has produced 82 unicorns and 17 public companies.
• With a record-low acceptance rate of 0.6% YC is now the most selective accelerator in the world. 
• AI dominates recent batches, functioning as a horizontal competency entrenched across B2B, SaaS, fintech, healthcare, and robotics rather than a standalone category. 
• The top four public YC alumni (Airbnb, DoorDash, Coinbase, and Instacart) account for more than 84% of all YC public company market capitalisation. 
• In 2025, YC moved from two to four batches per year, funding 140–200 companies per cohort. The Winter 2026 batch supported 196 companies at an acceptance rate of approximately 1%. 
• Private company valuations in the lower part of this list are based on last-round marks from 2021-2023 and should be treated as indicative only and may not reflect current fair market value, particularly given the market corrections of 2022–2024. .

Top 100 YC Companies

What are the top Y Combinator companies? Stripe, Airbnb, Cruise, Scale AI, DoorDash, Coinbase, Instacart, Dropbox, Rippling, and Flexport are among the largest and most successful companies backed by Y Combinator. The ranking below compares 100 YC companies based on total disclosed funding raised rather than current company valuation.

All figures represent total disclosed funding raised and exclude non-dilutive funding, government grants, and undisclosed round amounts. 

Rankings 27-100 mostly represent funding rounds that closed between 2019 and 2023. Many of these private company valuations have not been updated since those rounds and may not reflect current fair market value, especially for companies that were active in areas with peak valuations in 2021 and 2022. 

Sources: Eqvista proprietary research, Crunchbase, cbinsight, SEC EDGAR filings, and company press releases. Private company figures are subject to reporting lags and may not reflect the most recent financing activity.

Ranking Methodology

Companies are ranked by total disclosed funding raised, and cross-referenced against Crunchbase and PitchBook. The ranking metric is not current valuation or market capitalisation.

What Is Y Combinator and How Does It Work?

Y Combinator (YC) is a startup accelerator and seed-stage investor founded in 2005. It provides funding, mentorship, access to its founder network, and a structured program culminating in Demo Day. YC has backed more than 5,600 companies, including Stripe, Airbnb, DoorDash, Coinbase, Reddit, Dropbox, and Instacart.

Y Combinator is a venture capital firm that invests in businesses. Seed money is the first round of venture capital. While you’re getting started, it covers your expenses. Some businesses may only require an initial investment. Y Combinator (YC) is a technology startup accelerator in the United States that was founded in March 2005. Y Combinator is a business accelerator that invests twice a year in a diverse variety of startups. Stripe, Airbnb, Cruise, PagerDuty, DoorDash, Coinbase, Instacart, Dropbox, Twitch, Flightfox, and Reddit are just a few of the firms that have utilized it to launch.

Y Combinator Statistics and Trends in 2026

 Y Combinator has spent two decades doing one thing incredibly well: identifying and funding startups that go on to change the world. Its 2026 portfolio numbers demonstrate that track record, indicating the scale and influence of an accelerator that has evolved into a standalone institution. 

Y Combinator’s edge has never been the money, it’s the judgment. Over two decades of backing founders before the market saw what they saw, that judgment has built a portfolio approaching $600 billion in combined value.

Since 2005, Y Combinator has funded 5,668 distinct companies in 48 batches across two decades. Its portfolio companies have raised over $145 billion in follow-on funding, created 82 unicorns (companies worth more than $1 billion), and seen 17 go public via IPOs or direct listings. One out of every four YC unicorns has grown into a decacorn, worth more than $10 billion. 

Programme Structure and Deal Terms

The current YC deal provides $500,000 in seed funding for each startup, with $125,000 in exchange for 7% equity via a post-money SAFE and an additional $375,000 on an unlimited SAFE with most-favored-nation restrictions. Nonprofit organizations receive a $100,000 donation, with no equity taken out. The 11-week program culminates in Demo Day, during which founders pitch to hundreds of investors at once.

In 2025, YC expanded from two to four annual batches, with each cohort typically investing between 140 and 200 companies. The Winter 2026 batch funded 196 companies. With this structural adjustment, YC now invests funds in over 600 new startups each year, consolidating its position as the world’s largest institutional seed investor. 

How Hard Is It to Get Into YC?  

YC’s acceptance rate has declined dramatically as applications have increased. Each batch receives between 20,000 to 40,000 applications. The Summer 2025 cohort has the lowest acceptance rate ever recorded, at 0.6%, making YC statistically more selective than Harvard’s undergraduate admissions. The Winter 2026 rate was around 1%, which is still well below the 1.5 to 2% numbers typically mentioned in older sources. 

Which Sectors Dominate YC Today? 

The composition of YC batches has changed considerably in the last five years. AI is no longer a discrete sector, but rather a horizontal capability integrated into B2B SaaS, fintech, healthcare, developer tools, robots, and infrastructure. B2B SaaS remains the most popular company type, with 546 companies in the YC database labeled as both B2B and SaaS. Consumer-focused companies, which were previously an integral part of the YC core values, have practically disappeared from recent batches.

As of July 2026, YC had funded 2,623 B2B software and services companies, indicating a continued shift toward enterprise and professional markets. Founding team sizes have also decreased, with teams of three to five people now being the most typical starting configuration, thanks to AI-assisted product development and go-to-market tools. 

Where Do YC Startups Come From? 

The large majority of YC companies, 85% to 90%, are headquartered in the United States, with San Francisco, New York, and other major tech hubs serving as the primary headquarters. Despite years of forecasts about geographic decentralization in technology, San Francisco has been attracting YC founders at a record rate in recent cohorts, owing to the Bay Area’s concentration of AI talent and investor activity. 

FAQs about Y Combinator

Whether you’re a first-time founder or a seasoned entrepreneur, Y Combinator raises a lot of questions. Here are answers to the ones people ask most. 

What is Y Combinator’s acceptance rate in 2026?

Acceptance rates vary by batch and are not officially published. Based on available application and batch size data, the Summer 2025 rate was approximately 0.6%, the lowest on record. The Winter 2026 batch funded 196 companies from an estimated pool of 20,000 to 40,000 applications, implying a rate of roughly 1%. The commonly cited 1.5 to 2% figure is outdated.

How much does Y Combinator invest per company?

The current standard deal is $500,000 per company. This is structured as $125,000 for 7% equity via a post-money SAFE, plus $375,000 on an uncapped SAFE with most-favoured-nation provisions. Non-profit organisations receive a $100,000 donation with no equity taken. These terms have been updated several times since YC’s founding; older sources may reference the previous $125,000 standard deal.

How does the Y Combinator funding program work?

Y Combinator runs two batches per year Winter and Summer each lasting three months. Accepted startups receive funding in exchange for a small equity stake, along with access to YC’s network of mentors, investors, and alumni. Throughout the program, founders work intensively on their product, meet weekly with YC partners for guidance, and connect with fellow batch members. The program culminates in Demo Day, where startups pitch to a room full of top-tier investors. Beyond the batch itself, YC continues to support its alumni through its vast network, follow-on funding opportunities, and a community that spans thousands of companies worldwide. 

How many YC companies have gone public?

As of 2026, 17 YC-backed companies have gone public through IPOs or direct listings. These span fintech, enterprise software, consumer applications, and other sectors. Many more YC companies have been acquired rather than taken public, with notable acquisitions by Google, Meta, Apple, and other major technology companies.

Does Y Combinator fund companies outside the United States?

Yes. While 85 to 90% of YC companies are US-based, YC has funded companies from across the world. Notable international alumni include Rappi (Colombia), Razorpay and Groww (India), Meesho (India), Zepto (India), Wave Mobile Money (West Africa), and Paystack (Nigeria). YC’s international presence has grown steadily, particularly in India and Latin America.

Why do startups need Y Combinator or an accelerator? 

Building a successful startup takes more than a great idea: it takes the right support at the right time. Accelerators like Y Combinator give founders access to mentorship, funding, and networks that would otherwise take years to build on their own. Here’s how they make a difference:

• All-in-one support: Mentorship, funding, legal, and financial services all under one roof
• De-risking growth: Identifies hidden threats across product-market fit, hiring, and funding before they become costly
• Network access: Opens doors to investors and early customers when startups need them most
• Community and culture: Co-working spaces and curated events connect like-minded founders
• Global reach: Leverages a worldwide alumni network to help startups scale beyond borders

From YC Funding to Equity Management and Valuation

Raising capital is only one part of building a venture-backed company. As startups grow, they need to manage increasingly complex cap tables, employee equity, financing rounds, and company valuations.

Eqvista helps startups from early stage through pre-IPO manage their equity and valuation requirements, including cap table management, 409A valuations, business valuations, and financial reporting valuations.

Manage your equity and valuations with Eqvista. Contact us to find out more.