Series B

Definition

Series B is the scaling round after Series A, typically $20M to $40M, funding expansion of a go-to-market machine that already works.

How it comes up in fundraising

Series B diligence centers on efficiency: CAC payback, sales productivity, cohort economics, and whether growth persists as spend scales.

Frequently asked questions

What changes between Series A and B?

The question moves from “does the engine work?” to “does it scale efficiently?”; financial metrics dominate narrative almost completely.

What ARR is typical at Series B?

Commonly $5M to $15M ARR for software, with efficiency metrics mattering as much as the absolute number.

Cite this term

Round Funded. "Series B." Startup Fundraising Glossary.

Stable URL, it will not change: https://www.roundfunded.com/en/glossary/series-b

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