Invoice
In short
An invoice is a document a freelancer or contractor sends a client to request payment for completed work, listing the services, amount, and payment details.
A clean invoice states your name or business name, an invoice number and date, a description of the work and period covered, the amount due and currency, your payment details (bank or platform account), and the due date. Sending consistent, numbered invoices makes it easier to track what has been paid and gives you a paper trail for your own tax filing.
For remote contractors, agree on invoicing frequency (weekly, monthly, per milestone) and payment terms — for example net 15 or net 30 days — before starting work, so there is no ambiguity about when you get paid.