Subscriber funnel
Sign-ups by channel, the free list and the paid list.
By Surojit Chakraverti, founder of L3VLUP and an investor running a long-short healthcare and technology equities strategy.
On this subject: subscriber funnel.Updated 30 October 2026
What it does
The stocks and flows of a subscription audience. Sign-ups arrive by channel (organic, referral, paid acquisition, cross-promotion); the list loses unsubscribes and cleaned addresses; free readers convert to paid; paid readers cancel, some leaving the list and some returning to it as free readers. The free and paid lists are each rolled forward, and together they must equal the list every month.
Where it lives
The same schedule in each model that carries it, with the rows to open. Open a model in the browser, go to the sheet, and click the lines.
- Assumptions, rows 13–15: Free subscribers at the start, Paid subscribers at the start, Cash at the start
- Assumptions, rows 18–26: Organic sign-ups, month 1, Growth in organic sign-ups a month, base, Growth in organic sign-ups a month, upside, Growth in organic sign-ups a month, downside…
- Assumptions, rows 29–38: Unsubscribes a month, % of the list, List cleaning a month, % of the list, Free-to-paid conversion a month, base, Free-to-paid conversion a month, upside…
- Subscribers, rows 6–10: Organic, Referral, Paid acquisition, Cross-promotion…
- Subscribers, rows 13–15: Opening list, Unsubscribed and cleaned, Closing list
- Subscribers, rows 18–23: Opening free subscribers, Unsubscribed, Cleaned, Converted to paid…
- Subscribers, rows 26–29: Opening paid subscribers, Cancelled, Closing paid subscribers, Check: free + paid - total list
What a reviewer looks for
- Paid subscribers as a fixed share of the list.
- Conversion applied to the whole list, paid readers included.
- Cancelled paid readers removed from the list when most stay as free readers.
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