How is this different from milestone billing?
Milestone billing splits the work into stages and invoices each one as it is delivered. A payment plan splits a single invoice for work already done into instalments. One is a billing structure, the other is a payment arrangement.
Does this need a credit licence?
Informal instalment arrangements without interest or charges are generally not regulated consumer credit, but arrangements with fees or over longer terms can be. If you offer structured finance regularly, take advice — and see Gaffer's customer financing for third-party options.
Can the customer pay instalments online?
Yes. Payment links and the invoice payment portal work alongside plans, so the customer can pay each instalment by card rather than needing to be chased for a transfer.
What happens if they stop paying?
Cancel the plan and the invoice goes back into normal collections, where Gaffer's invoice reminders and collections radar handle it as an overdue debt.