Incusia

Incusia is invoicing for solo freelancers and contractors who send their own invoices. Every plan has unlimited invoices and clients, and the monthly price you sign up at is written into the Terms of Service, so $9 now is still $9 in 2031.

Create an invoice or an estimate your client signs in the browser, send it, and see when it is delivered and opened. If it isn't paid, a reminder goes out on its own. Clients pay by card, Apple Pay or bank transfer from a button on the invoice, with no login.

Pro adds recurring invoices, late fees, deposits, time tracking, receipt scanning and a cash forecast. Cancelling is one click, with PDF and CSV export.

Plans: $9 a month, $29 a month for Pro, or $99 once for Lifetime. 7-day trial with full Pro access, no card needed.