Kit vs Substack: flat fee or 10% of your revenue?

Like beehiiv, Kit charges a flat monthly fee and takes 0% of your subscriptions. Substack takes 10% of everything you earn but has no flat fee. Which wins depends entirely on how much you make — here's the exact crossover.

Fees verified 2026-07-13 from official sources.

The core difference

How each platform charges (2026-07-13)
PlatformPlatform feeCut of subscription revenueProcessing
Substack$0/mo10%Stripe 2.9% + $0.30
Kit Creator$39–$679/mo (by list size)0%Stripe 2.9% + $0.30

Where Kit overtakes Substack (the crossover)

Kit is cheaper once your yearly paid revenue crosses ~10× Kit's yearly fee. Using Kit Creator's annual-billing rate (annual = 10 months) at each list size:

Break-even annual paid revenue: above this, Kit Creator costs less than Substack's 10%
List sizeKit Creator /yr*Substack cheaper belowKit cheaper above
1,000~$390< $3,900/yr revenue> $3,900/yr
5,000~$890< $8,900/yr> $8,900/yr
10,000~$1,390< $13,900/yr> $13,900/yr
25,000~$1,990< $19,900/yr> $19,900/yr

*Kit Creator monthly rate × 10 (annual billing = 2 months free). Crossover ignores Stripe fees since both charge the same processing. Note: Kit's flat fees run higher than beehiiv's, so Kit's crossover sits a bit lower — but if you're comparing all three, beehiiv vs Substack is usually the cheaper flat-fee option.

When each wins

Check your exact numbers

Use the calculator for Kit's flat cost at your list size, then apply your paid-revenue figure against the crossover table. Want the full picture across all three platforms? See the complete pricing comparison.

Sources

Kit: Creator tier fees from kit.com pricing engine, 2026-07-13. Substack: 10% platform fee + Stripe 2.9%+$0.30 from official support docs, 2026-07-13.

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