Invoice vs estimate vs quote vs receipt
They all list prices and line items, so they get used interchangeably — but they are four different documents that do four different jobs at four different points in a sale. Sending the wrong one costs you money or credibility. Here is how they differ.
The short answer
| Document | Sent | Purpose | Price is |
|---|---|---|---|
| Quote | Before the work | A fixed price offer | Firm — you commit to it |
| Estimate | Before the work | An approximate price | A best guess — can change |
| Invoice | After / on delivery | A request for payment | What is owed, due by a date |
| Receipt | After payment | Proof it was paid | What was paid, already settled |
Quote: a firm price, before the work
A quote is a formal offer to do a defined job for a specific, fixed price. Once the client accepts it, you are generally expected to honor that number even if the work turns out harder than you thought — which is exactly why clients like them. Use a quote when the scope is clear and you are confident in your pricing. It is your pricing commitment in writing.
Estimate: an approximate price, before the work
An estimate is your best educated guess at the cost when the scope is not yet nailed down — "roughly $2,000–$2,500 depending on how many revisions." It sets expectations without locking you in. Use an estimate for open-ended work: renovations, debugging, anything where the final number genuinely depends on what you find. The key word, which belongs on the document, is estimate: it signals the number may move.
Quote or estimate? If you would be comfortable being held to the number, send a quote. If the honest answer is "it depends," send an estimate and say what it depends on.
Invoice: the request for payment
Once the work is done (or hits an agreed milestone), the invoice is how you actually ask to be paid. It carries a unique number, itemizes what was delivered, states the total owed, and — crucially — sets a due date. Unlike a quote or estimate, an invoice creates an expectation of payment by a specific time and becomes part of both parties' financial records. This is the document you chase if it goes unpaid. Learn how to write one.
Receipt: proof of payment
A receipt is issued after the client has paid, confirming the transaction is complete. It is the client's proof of purchase — for their records, expense claims, or taxes. Where an invoice says "you owe this," a receipt says "this is settled." Many businesses simply stamp the paid invoice as a receipt, which is perfectly standard.
How they flow through a job
On a typical project the documents come in order:
- The client asks what it will cost. You send a quote (firm) or an estimate (approximate).
- They accept. You do the work.
- You send an invoice for the agreed amount, with a due date.
- They pay. You issue a receipt (or mark the invoice paid).
Not every job needs all four — a quick gig might be just an invoice and a receipt — but knowing which is which keeps you from, say, sending an "estimate" when the client expected a firm price, or an "invoice" for work you have not agreed to yet.
Because these are really the same document with a different label and intent, a good generator lets you switch the document type with one setting. In Billotter that is the document-type control at the top of the sheet — pick invoice, estimate, quote or receipt and the heading and wording follow.
Frequently asked
Is a quote legally binding?
Once a client accepts a quote, it generally forms the agreed price for the defined scope, and you are expected to honor it. An estimate is not a firm commitment — it explicitly signals the final figure may change. Exact legal treatment varies by jurisdiction and what your terms say.
What is the difference between an estimate and a quote?
A quote is a fixed, firm price you commit to for a defined job. An estimate is an approximate figure for work whose scope is not fully known, and it can change as the job is clarified. Use a quote when scope is clear, an estimate when it depends.
Is an invoice the same as a receipt?
No. An invoice is a request for payment sent before the client pays and includes a due date. A receipt is proof of payment issued after they pay. A common shortcut is to stamp the invoice PAID and reuse it as the receipt.
Do I send an invoice or a receipt first?
The invoice comes first — it asks for payment. The receipt comes after the client has paid, confirming the money was received. In between, the invoice is the document you follow up on if payment is late.
Keep reading
- How to write an invoiceThe 8 parts, step by step, with an example
- Invoice payment terms explainedNet 30, Net 15, Due on Receipt & how to choose
- How to invoice as a freelancerYour first invoice, taxes, getting paid — no software
← Billotter: the free, private, in-browser invoice generator