Divide five million by one hundred thousand. You get fifty.

That is the crude arithmetic sitting underneath every "start a paid newsletter" webinar currently being sold to coaches.

Substack announced five million paid subscriptions on March 11, 2025. Eighteen months later the company is still presenting the same headline number. In data released in May 2026, readers were described as paying for more than five million subscriptions to Substack publishers. Substack passed 5M paid subscriptions in March 2025, and as of May 2026 reporting it was still described as "5m+" with no confirmed 6M mark, which independent analyst Simon Owens reads as deceleration.

The supply side did not stay still. As of April 2026, nearly 100,000 publications earn money globally on Substack, up from 50,000 in May 2025, with almost 30,000 outside the US.

Same pie. Twice the forks.

What the average actually hides

Fifty paid subscribers per monetizing publication is a mean, and means lie badly in creator economies. The top of the platform is enormous. Over 50 people are making more than $1 million a year on Substack. Every dollar they hold is a dollar not sitting in the median.

A better shape-of-the-market number: 10,000 publications have crossed 1,000 paid subscribers. Against nearly 100,000 monetizing publications, that is one in ten.

One more thing worth knowing before you quote a stat in your own launch email. A fabricated "8.4M paid subscriptions" figure circulates with no primary source at all. It appears in round-ups that look authoritative. It is not a Substack number.

Where the conversion math gets interesting for coaches

This is the part that should change how a coach prices, not whether they publish.

On beehiiv, platform median free-to-paid conversion is 0.62%, but the top decile of economy newsletters converts at 30.8%, finance at 20.0% and investing at 18.69% — vertical focus, not audience size, is what separates the leaders.

Substack's own pattern points the same direction. The average paid conversion rate on Substack is 3%, specialized and niche publications convert at 4-10%, and the tech category leads all categories at 8%.

Narrow beats big. A generic "leadership and mindset" letter competes with everything. A letter for clinic owners hiring their first associate competes with almost nothing.

The fee line nobody mentions

Substack takes a 10% platform fee on paid subscription revenue, and Stripe takes a processing fee on top, which is why gross and take-home differ by roughly 15%.

Run it. A thousand paid subscribers at $8 a month is around $8,000 gross and roughly $6,800 in the account. That is a real business, and it is also a number only about a tenth of monetizing publications have reached.

Meanwhile, 40% of Substack publications are free-only, which is either an untapped opportunity or a lot of writers who tried the paywall math and declined.

For a coach with a $4,000 program, the honest use of a paid tier is rarely the subscription revenue. It is a qualified, paying, self-selected list of people who have already proven they will send you money. Price it as a filter. The $50-a-year tier that produces four discovery calls a month outperforms the $200 tier that produces silence.