Substack Pro flips the writer's split, but only for a year

The revenue mechanism

Substack Pro is a selective arrangement, separate from the platform's standard self-serve terms, in which Substack itself pays a writer an upfront sum and then keeps a larger share of that writer's subscription revenue for a period. Substack co-founder Hamish McKenzie first described the mechanism publicly in a company blog post dated 12 March 2021, titled Why we pay writers. The post says Substack had earlier experimented with smaller advances of $10,000 to $30,000, repaid through revenue sharing, before restructuring the idea into the branded Substack Pro programme: a writer is paid an upfront sum covering a first year on the platform, and in exchange Substack keeps 85% of that writer's subscription revenue during that year.

What the documents show

The same post states that after the guaranteed first year, the arrangement reverses: the writer keeps 90% of subscription revenue from then on, the same split available to any writer who never took an advance. McKenzie describes Substack Pro as 'still only a few months into this' as of the March 2021 disclosure, meaning the branded 85/90 structure was new even though informal advances predated it by an unspecified period. A contemporaneous Recode report by Peter Kafka, published a week later, independently confirms the 85/90 split and adds that Substack also offered legal support and healthcare stipends to some Pro writers, while writers criticised the company for not disclosing which of them held Pro deals.

The assumptions exposed

Substack's own account frames these as 'business decisions, not editorial ones,' stating the company does not commission, edit, or manage the writers it pays. That framing is the company's characterisation, not an independently verified fact; there is no audited list of who received deals or how much they were paid, and Substack states plainly that it does not disclose recipients' names. The 85% first-year share is also easy to misread: it applies only to writers who accepted an upfront advance, not to the standard 90% terms most writers on the platform use, so a reader encountering 'Substack Pro' should not assume it describes ordinary Substack economics.

What to check before you rely on it

A writer or reader evaluating Substack Pro claims should separate the advance mechanism from the platform's general fee structure, and treat any specific dollar figure for a named writer as coming from that writer or a reporter, never from Substack, which does not publish deal terms. This is an editorial checklist beyond what either cited document states outright.

• Is a cited Substack Pro figure attributed to Substack itself, to the writer, or to unnamed sources?
• Does the claim describe the guaranteed first year (85% to Substack) or the ordinary terms that follow (90% to the writer)?
• Has the writer or Substack confirmed the deal publicly, given that Substack states it will not name recipients without their consent?

The programme's existence is well documented by Substack's own account; the specific economics of any individual deal generally are not.