Series A, B, C, and D

Series A, B, C, and D are sequential rounds of venture capital funding that a startup raises after its seed round, with each round corresponding to a different stage of the company’s growth and each one diluting the founders’ ownership further. The average Series A is $18.7 million, Series B runs $27 to $30 million, and Series C frequently exceeds $50 million, though what the company must prove at each stage matters more than the dollar amount.

What Each Round Means

Series A: prove the product works

Series A is the first major institutional round after seed, and it funds the transition from “we have a product” to “we have a business.” Investors want to see product-market fit, which usually means consistent revenue growth, strong retention, or a clear path to both. The median dilution at Series A is 20.5%, meaning founders give up roughly a fifth of the company on top of what they already gave up at seed. Only 46% of seed-funded companies ever reach this stage.

Series B: prove the business scales

Series B funds expansion: hiring, new markets, building infrastructure to handle 10x the volume. The median round is $27 to $30 million with 16.7% dilution. Companies that reach Series B have a dramatically higher survival rate, with roughly 99% making it past this stage, because by now the business model is validated and generating real revenue. The valuation jump from A to B is typically 2 to 3x.

Series C and beyond: prepare for the endgame

Series C and D rounds fund the final push toward an IPO or acquisition. These rounds frequently exceed $50 million and sometimes reach hundreds of millions. At this stage the investors are often growth equity firms or crossover funds rather than traditional VCs, and the terms become more complex. By Series C, most founders own 15 to 25% of the company they started.

Real Example

Glossier raised its way through the full alphabet: a $2 million seed from Forerunner Ventures in 2013, an $8.4 million Series A from Thrive Capital in 2014, a $24 million Series B from Index Ventures in 2016, a $52 million Series C in 2018, a $100 million Series D from Sequoia Capital at a $1.8 billion valuation in 2019, and an $80 million Series E in 2021. By the time the D round closed, founder Emily Weiss owned a fraction of the company that started as her blog, and the board dynamics that came with six rounds of institutional funding eventually contributed to her stepping down as CEO.

Go Deeper

• Venture Capital: The full picture of how VC works, what term sheets contain, and the gender funding gap.
• Seed Round: The first round of funding that comes before Series A.
• Dilution: How each funding round shrinks the founder’s ownership stake.
• Valuation: How investors determine what a company is worth at each stage.

Frequently Asked Questions

What is the difference between Series A, B, C, and D funding?

Each letter represents a sequential round of venture capital at an increasing company stage. Series A ($18.7 million average) proves the product works, Series B ($27 to $30 million) proves the business scales, Series C ($50 million+) prepares for an exit, and Series D is typically a final round before IPO or acquisition. Each round dilutes existing shareholders by 15 to 21%.

How much equity do founders lose in each round?

Median dilution per round: 20.5% at Series A, 16.7% at Series B, and 10 to 15% at Series C and beyond. Combined with the 20 to 30% given up at seed, a founder who started with 100% typically holds less than 30% after Series B and 15 to 25% after Series C, before accounting for employee option pool refreshes that dilute founders further.

What percentage of startups make it from Series A to Series B?

Roughly 65% of Series A companies successfully raise a Series B, with about 35% failing before they get there. Past Series B, the survival rate jumps dramatically to approximately 99%, because by that point the company has a proven business model and meaningful revenue.

Do all startups need to raise Series A through D?

Most businesses never raise venture capital at all, and many successful VC-backed companies exit before reaching Series D. Drunk Elephant sold to Shiseido for $845 million without raising a single institutional round. The number of rounds a company raises depends on how capital-intensive the business is and whether the founders want to pursue a large-scale exit or build a profitable company at a smaller scale.

Sources

• Carta, “Dilution Data Q1 2024,” 2024. Median dilution rates by funding round.
• Fundz, “Series A, B, and Beyond,” 2024. Average round sizes by stage.
• Crunchbase, “US Median Round Size,” 2024. Series B benchmarks and survival rates.