Almost no YC startup raises a Series A within a year of Demo Day
Published 29 October 2026
The story people tell about Y Combinator is that a good company walks off the Demo Day stage, closes a seed round and raises its Series A within the year. We went looking for those companies batch by batch and found very few.
Of 2,916 companies in the YC batches from Winter 2021 to Summer 2025, 23 have a Series A in Crunchbase dated within 12 months of their Demo Day. That is 0.8%. Our method misses some fast raisers (see below), but even if every company it could miss had raised in its first year, the share would be 2.8%.
By batch
| Batch | Companies | Series A within 12 months | Share | Ceiling |
|---|---|---|---|---|
| Winter 2021 | 335 | 7 | 2.1% | 7.2% |
| Summer 2021 | 391 | 4 | 1.0% | 3.8% |
| Winter 2022 | 398 | 3 | 0.8% | 3.5% |
| Summer 2022 | 233 | 1 | 0.4% | 1.7% |
| Winter 2023 | 274 | 2 | 0.7% | 2.9% |
| Summer 2023 | 220 | 0 | 0.0% | 2.3% |
| Winter 2024 | 248 | 0 | 0.0% | 1.2% |
| Summer 2024 | 248 | 1 | 0.4% | 1.2% |
| Fall 2024 | 94 | 0 | 0.0% | 0.0% |
| Winter 2025 | 165 | 1 | 0.6% | 1.2% |
| Spring 2025 | 144 | 4 | 2.8% | 2.8% |
| Summer 2025 | 166 | 0 | 0.0% | 0.0% |
Winter 2021, the batch that demoed into the 2021 funding boom, had the most: Houm, Tint, Coderhouse, Trela, Aviron Interactive, Mono and Moonshot Brands. Moonshot Brands' round was $160M. After that the count drops to between zero and three a batch, and Summer 2023 and Winter 2024 have none.
Then Spring 2025, YC's first spring batch, put four companies over the line: Sygaldry Technologies ($105M), Lucis ($20M), Auctor ($20M) and Sim ($7M). At 2.8% it is the highest share in the table, above Winter 2021's 2.1%. Summer 2024 had one, Diode Computers ($11.4M), and Winter 2025 had one, Harper ($47M).
When they do raise it
Most YC companies never show a Series A at all. Of the 2021 to 2025 batches above, 10.4% have a Series A or a later round today. For the 2016 to 2020 batches, which have had longer, it is 25.7%.
Among companies from the 2021 to 2023 batches whose latest round is a Series A, 195 of them, the typical round came 35 months after Demo Day. Only 17 of the 195 came inside the first year. The 2023 batches have had at most about three and a half years, so that median will move later as more of them raise.
How we counted
We took Y Combinator's public company directory (batch and website for each company) and matched it to Crunchbase by domain. For Demo Day we used one date per season: 25 March for winter batches, 15 June for spring, 31 August for summer and 10 December for fall. The Crunchbase data was read on 29 October 2026; its newest round is dated 22 October 2026. Batches whose 12 months had not run out by then are left out.
Crunchbase keeps only a company's latest round with a date. A company counts when its latest round is a Series A or later and is dated no more than 12 months after Demo Day. A company that raised its A in month 8 and its B in month 20 shows only the B, so we miss it. The "Ceiling" column adds every company whose latest round is a Series B or later dated after the 12 months, as if all of them had raised their A early. Companies with no Crunchbase match count as having no Series A, and Crunchbase misses some rounds, so both columns can run low.
For batches before 2021 too many companies have moved past their Series A for this method to say much: the ceiling for 2016 to 2020 is 13.5% against 0.9% counted. That is why the table starts in 2021.
Data: by batch, 2016 to 2025 and the companies counted.