Freelancers and small businesses sometimes send an invoice when they meant to send a quotation, and it causes exactly the confusion you'd expect — a client thinks they're being asked to pay for work that hasn't even been agreed to yet.
| Quotation | Invoice |
|---|---|
| Sent before work begins | Sent after work is done or delivered |
| Proposes a price, not yet owed | Requests payment that's now owed |
| Usually has a validity/expiry date | Has a payment due date |
| Can be negotiated or revised | Reflects agreed, final terms |
Why the order matters
A quotation gives the client a chance to approve, negotiate, or decline before any commitment is made on either side. Skipping straight to an invoice removes that step entirely, which can feel presumptuous even when the price itself is fair.
What happens after a quote is accepted
Once a client agrees to a quotation, that's the trigger to start work — and later, to generate the invoice using the same line items and pricing, so there's no discrepancy between what was quoted and what's billed.
A quotation isn't a legally binding promise to pay
Unlike an invoice, a quotation typically doesn't create a payment obligation on its own — it's an offer. This is exactly why it needs a validity period; without one, a client could try to accept an old price months later after your costs have changed.