The Y Combinator success rate (new research)

There is no single Y Combinator success rate. The answer depends on how you define success. Of the roughly 6,633 companies YC has backed since 2005, 662 (9.98%) have exited through an acquisition or IPO so far. But that headline figure counts every acquisition as a win, from billion-dollar deals to small acqui-hires, and most of YC's portfolio is still too young to have an outcome. By stricter measures, 21 companies (0.32%) have gone public and 118 (1.78%) have become unicorns.

In this research report, we’ll explore which sectors those successful companies belong to, what kind of exits they completed, and how many eventually became Unicorns.

We’ll also discuss which types of Y Combinator companies have historically had the highest failure rate and which are experiencing the most success in 2026.

Key Takeaways

1. By the broadest measure, any exit through M&A or an IPO, 9.98% of Y Combinator companies have succeeded so far. That figure treats every acquisition as a success, including small acqui-hires.
2. By stricter measures, 0.32% of YC companies have gone public and 1.78% (118 companies) have become unicorns. Among older batches that have had time to mature, outside research puts the unicorn rate at roughly 4.5%.
3. The top sectors of the 641 Y Combinator companies that have been acquired include software and SaaS, entertainment and social media, consumer and mobility, and FinTech.
4. 34 Y Combinator companies have been acquired in 2026 so far, with 76% of them in the enterprise software, FinTech, and healthcare sectors.
5. Most of Y Combinator’s failed investments were in the healthcare, FinTech, and transportation and logistics sectors.
6. Y Combinator is continuing to invest in B2B companies, with a heavy emphasis on AI startups, especially in the agentic AI space.

1. What is the Y Combinator success rate?

Since its inception in 2005, Y Combinator has become the gold standard for startup accelerators. It’s invested in roughly 6,633 companies to date, including some of the most valuable technology companies in the world.

What counts as a “successful startup” depends on the definition you choose, and the choice changes the answer a lot. Here are three common measures, from broadest to strictest:

• Any exit (M&A or IPO): 9.98%. 641 companies have been acquired or merged and 21 have gone public: 662 of 6,633. This is the most generous measure because it counts every acquisition as a success. Many startup acquisitions are acqui-hires or soft landings, where a struggling company is bought mainly for its team with little or no return for investors, so this figure overstates financial success.
• Unicorn status: 1.78%. 118 companies have reached a valuation of $1 billion or more (see section 2).
• IPO: 0.32%. 21 companies have gone public, the strictest common definition.

The denominator matters too. All three rates divide by every company YC has ever funded, including thousands from the last few batches that haven’t had time to exit or fail. With 84.23% of the portfolio still listed as active, these are outcomes so far, not final outcomes. Looking only at mature batches gives a fairer picture: an analysis of 4,939 YC companies in Lenny’s Newsletter found that roughly 4.5% become unicorns, compared with about 2.5% of other venture-backed seed-stage startups.

Failures are likely undercounted as well. Only 5.79% of the portfolio (384 companies) is formally listed as inactive, bankrupt or sold for its assets, but startups often stop operating without their listed status changing. The same Lenny’s Newsletter analysis put the share of YC companies that have gone out of business at 13%.

Here is how Y Combinator’s portfolio breaks down by current listed status. Remember that “Merged or Acquired” includes outcomes of every size, and “Active” includes companies that may have quietly stopped operating.

2. How many Y Combinator companies became Unicorns?

In the world of venture capital (VC), a Unicorn refers to a startup that has achieved a private valuation of at least $1 billion. Reaching this status is the primary goal for many ambitious founders, but it remains a vanishingly rare feat.

Of the 6,633 startups that Y Combinator has backed since 2005, just 118 companies have successfully become Unicorns. This represents a conversion rate of approximately 1.78% across the accelerator program’s portfolio. Because that denominator includes thousands of recent startups that are still early, the rate among mature batches is higher, at roughly 4.5%.

These Unicorns include several of the world’s most successful technology companies in recent history. Notable examples include:

3. What are the top sectors of the companies that got acquired?

Of the 641 Y Combinator companies that have successfully completed M&A exits since 2005, the software and software-as-a-service (SaaS) sector has been responsible for the largest number of transactions.

These deals have involved everything from infrastructure startups to enterprise software companies. Notable examples include Weebly’s $365 million acquisition by Square in 2018 and Salesforce’s $212 million acquisition of Heroku, announced in 2010.

The entertainment and social media sector has had the second-highest exit volume, largely driven by content platforms and gaming companies. It also saw one of the most lucrative exits in Y Combinator history in Twitch’s $970 million deal with Amazon.

There has also been significant historical demand for developer tools and engineering infrastructure, as well as for consumer mobility startups. The latter was responsible for Y Combinator’s top deal by exit value: General Motors’ 2016 acquisition of Cruise, widely reported at about $1 billion including earn-outs (GM said it paid about $581 million up front).

Lastly, FinTech has seen smaller total numbers than these other top sectors, but its activity has been growing more rapidly in recent years.

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4. Which types of companies are getting acquired in 2026?

Market trends and investor sentiment heavily influence startup acquisition activity, with focuses often shifting as new technologies emerge. So far, Y Combinator company acquisitions in 2026 reflect this pattern.

There were 34 deals completed this year to date, and 26 (76.47%), took place in the following sectors:

• Enterprise software and developer tools
• Financial technology (FinTech) and services
• Healthcare and wellness

Enterprise software and developer tools led the pack with 11 total acquisitions. Notable deals included ClickHouse and ServiceNow’s acquisitions of Langfuse and TraceLoop, both of which are large language model (LLM) engineering platforms.

FinTech and financial services were close behind with nine acquisitions. Two standouts included Capital One’s acquisition of the popular spend management platform Brex, as well as Kraken’s purchase of Magna, a digital asset and token management company.

Meanwhile, healthcare and wellness has seen six acquisitions. These deals largely targeted operational efficiency and workflow automation companies, such as CareRev, a healthcare staffing platform serving hospitals.

5. What were the sectors of Y Combinator companies that failed?

Y Combinator outperforms most of the startup market, but it isn’t without its share of failed investments. To date, 384 (5.79%) of its companies are formally listed as inactive, bankrupt or sold for their assets, and the true failure rate is likely higher (see section 1).

While industry data isn’t readily available for all of these companies, many of them operated in the following sectors:

• Healthcare: This mirrors the broader VC-backed market, where healthcare and biotech account for 14.4% of startup failures. Examples include Ruth Health, a maternal health services company, and Lucira Health, which offered at-home molecular testing.
• FinTech: This too is representative of the market at large, as FinTech companies are responsible for the second-highest share of startup failures at 13.2%. Typical examples include Capway and LendUp, online banking and lending platforms.
• Transportation and logistics: This sector represents 5.3% of startup failures, with many failing due to their high operating costs. One notable example was Convoy, which Y Combinator backed through its growth-stage Continuity fund rather than the accelerator program. A Unicorn several times over, it reached a Series E round and achieved a peak valuation of $3.8B before going under.

A significant portion of Y Combinator’s failed startups also operated in the food and agriculture sector—which accounts for 12.5% of startup failures generally—as well as the hardware and mobility sector.

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6. What is Y Combinator investing in now?

Y Combinator has selected 442 startups for seed funding across its most recent batches. This includes those slotted for investment in Fall 2025, Winter 2026, Spring 2026, and Summer 2026.

Of these, 284 are B2B software companies, representing a significant majority (64.25%). The industrial sector is a distant second with 50 companies (11%), while healthcare and consumer companies are tied for third at 33 (7.5%).

That said, artificial intelligence (AI) is clearly the real theme of Y Combinator’s current investment strategy. Roughly 49% of these companies have the terms "AI," "agent," "copilot," "LLM," or "machine learning" in their one-line description on Y Combinator.

Specifically, there’s a heavy emphasis on agentic AI, with 22% using language related to the technology. Most of this subset is focused on building AI agents, providing the infrastructure they need, or offering them directly.

There’s also a notable shift toward vertical AI, aiming to edge out the competition by niching down. Dozens of these AI company tools are exclusively for a single industry, such as restaurants, commercial lenders, and semiconductors.

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