Many creators treat every fee as the same cost. They are not. Payment processors charge a transaction fee almost everywhere you get paid. Platform commissions sit on top of that, and they are optional when you pick where you publish.
A processor fee is what Stripe, a bank, or a crypto rail takes to move money. That fee pays for the transfer itself. You will see some version of it on most paid products, including places that say publishing is free.
A platform commission is different. It is a cut of each paid reader or sale taken by the site where you host the work. On Substack that commission is 10 percent of creator earnings on paid subscriptions. On Serey the commission on creator earnings is 0 percent. Creators still pay processor transaction fees.
The practical difference shows up when support grows. Processor fees scale with each payment. A platform commission scales with every paid reader for as long as you stay. If you can keep the work somewhere that does not take a platform cut, more of the support stays with the writing.
Before you renew another year on a high-cut platform, separate the two lines on paper. One line is the cost of moving money. The other is the rent the platform charges on your paid audience.
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