Series A vs Series B: Metrics, Terms & Investor Bar (2026)

Series A vs Series B: What Changes at the Growth Stage (2026)

Series A is about proving a repeatable channel. Series B is about proving the machine scales. The metrics bar, the check size, and the investors are all different.

Series A reality

$8-15M priced round, $40-80M post. ~$1M ARR growing 3x, one repeatable acquisition channel, real retention data.

Series B reality

$20-50M priced round, $150-400M post. $5-10M ARR, 2-3x growth, gross margin visibility, and an efficient CAC payback.

What breaks between A and B

Most A-funded startups stall at $3-5M ARR. The B bar has moved up; plan 24 months of runway and a clear channel scale story before you leave the A.

Frequently asked questions

What ARR is required for Series B in 2026?

$5-10M ARR growing 2-3x is the typical bar. Below $3M ARR most B leads pass.

Do Series A leads always follow into B?

Usually pro rata, not lead. Expect a new lead investor at B.

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