The median Series A deal size of US-based startups was $8.6M between 2018 and late January 2020, according to an analysis of 2,539 Series A rounds in the US
Jason D. Rowley / Crunchbase News :
Context & Ripple Effects
This analysis of 2,539 US Series A rounds lands on top of a decade-long ratchet in early-stage check sizes. The number of $5M+ seed rounds climbed from 45 in 2014 to 180 in 2018, and follow-on analysis shows seed rounds getting structurally bigger — $3M+ deals went from 7.8% of the total in 2015-17 to 17% in 2018-20.
So an $8.6M median Series A is less a standalone figure than the downstream price of inflated seeds: companies arrive at their A with more capital already raised and higher bars to clear. The same pressure shows up on the pricing side, where Pitchbook later found the median US Series A pre-money valuation had risen sixfold to $37M since 2010.
First-order effects
- Founders raising a Series A now compete against a median of $8.6M, meaning sub-median rounds risk looking undercapitalized next to peers carrying twice the runway.
- Investors writing A-round checks must commit roughly double the classic $4-5M benchmark per deal, stretching fund capacity or forcing fewer positions per portfolio.
Second-order effects
- Seed-stage funds face a blurred boundary: with $3M+ seeds now common, their portfolio companies enter Series A priced like former B-round candidates, pushing seed investors toward larger reserves for follow-on pro-rata.
- Mid-market check writers get squeezed from both ends — TechCrunch's decade review found <$1M rounds shrinking while $10-20M rounds grow, hollowing out the traditional small-A slot the $8.6M median sits above.
Third-order effects
- If seed and Series A keep inflating together, early-stage venture consolidates around fewer, larger rounds per company — concentrating capital in fewer startups and raising the cost of entry for new micro-funds competing at those stages.
- Larger medians at every pre-Series-B stage make the mega-round pipeline downstream harder to sustain, since each company arrives at growth stages having consumed more capital to reach the same milestones.
The trend: US early-stage venture is undergoing sustained check-size inflation, with seed and Series A rounds converging upward and redefining what a 'normal' first institutional round looks like.