A quote offers a price before the work starts. An invoice asks for payment after the work is done. A receipt confirms the payment arrived. A proforma invoice sits between the quote and the invoice: it shows what the final invoice will say, so the client can approve the spend or pay in advance. You send them in that order.
Mixing them up costs you time. A client who receives a quote labelled "invoice" may pay it before the price is final, and a client who asks for a receipt usually needs one for their own records. This guide gives the one-line answer for each document, compares them in a table, and then follows one plumbing job through every document from first price to final payment.
What is the difference between a quote, an invoice and a receipt?
Each document answers a different question for the client:
- A quote answers "what will this cost?" It is sent before the work and does not ask for payment.
- A proforma invoice answers "what will the invoice say?" It is sent before the work or delivery, in invoice format, when the client needs it to approve or prepay.
- An invoice answers "what do I owe, and by when?" It is sent after the work and asks for payment by a due date.
- A receipt answers "did my payment arrive?" It is sent after payment and confirms the amount, the date and the method.
A related document, the credit note, corrects an invoice you already sent. It comes up later in this guide.
How do quotes, proformas, invoices and receipts compare?
| Quote | Proforma invoice | Invoice | Receipt | |
|---|---|---|---|---|
| Purpose | Offer a price | Preview the final invoice | Request payment | Confirm payment |
| When you send it | Before the work | Before the work or delivery | After the work | After payment |
| Asks for payment? | No | Only if it says payment in advance is required | Yes, by a due date | No, payment is done |
| Binding? | Can become part of the agreement once the client accepts | No, it is a preview | Records a debt the client owes | Records that the debt is paid |
| Recorded as a sale? | No | No | Yes | No, it records the payment |
| Typical number | Q-0058 | PF-0058 | INV-0213 | Quotes the invoice number |
Whether an accepted quote binds both sides depends on your contract and where you work. In England, Citizens Advice describes a quote as "a promise to do work at an agreed price" and says the trader can't charge more without a good reason, such as extra work the customer agreed to. This is general information, not legal advice. Rules vary by state and country.
What is the difference between an invoice and a receipt?
An invoice asks for money and a receipt confirms you received it. The invoice goes out when the work is done and shows the total due and the due date. The receipt goes out after the client pays and shows the amount paid, the payment date, the payment method and the invoice it settles.
For the client, the invoice is what they approve and pay. The receipt is their proof that they paid. For you, the invoice is the record of the sale. The IRS lists both among the supporting documents a business should keep, alongside deposit slips and canceled checks.
A paid invoice can work as a receipt. Many small businesses send the original invoice back marked "Paid" with the payment date and method. That is enough for most clients. Send a separate receipt when the client asks for one, or when they paid in cash and have no bank record of the payment.
What is the difference between a quote and an invoice?
A quote comes before the work and sets the price. An invoice comes after the work and asks for that price to be paid. If the client accepts a quote for $1,590, the invoice should normally say $1,590, plus any extra work the client agreed to along the way.
Three details keep the two documents apart:
- Label each one clearly. Put "Quote" or "Invoice" as the largest word at the top. A client who pays a quote by mistake creates a refund and a mess in both sets of books.
- Give the quote an expiry date. Material prices change. "Valid for 30 days" protects you if the client accepts three months later.
- Reference the quote on the invoice. "As per quote Q-0058" lets the client's approver match the two in seconds.
If you need to price a job quickly, the free quote generator builds a quote as a PDF, and the invoice generator does the same for the invoice that follows it.
Is an estimate the same as a quote?
No. An estimate is your best guess at the cost, and the final bill can move from it. A quote is a firm price for the scope it describes. Citizens Advice draws the same line for England: with an estimate, the final price should be "reasonable", while a quote holds unless there is a good reason to change it.
Use an estimate when you can't see the full job yet, such as a leak behind a wall. Use a quote when the scope is clear. Many trades send an estimate first and a quote once they have inspected the site. If you quote often, our page on estimate software shows how quotes turn into invoices without retyping.
What is the difference between a proforma invoice and an invoice?
A proforma invoice is a preview. The invoice is the real bill. A proforma lists the same items, prices and terms the final invoice will have, but it is not recorded as a sale and, in most cases, it does not demand payment. The invoice is the document the client pays against and the one you keep for tax.
Clients ask for a proforma in two situations. Their finance team needs a priced document to approve the spend or raise a purchase order, or you want payment before you start and the client needs something in invoice format to pay from. Mark it "Proforma invoice" and, if you sell in a VAT or GST country, add that it is not a tax invoice. The glossary entry on the proforma invoice has a full example. For upfront payment terms such as CIA and PIA, see our guide to payment in advance.
How do the documents fit together on one job?
Here is one job traced from the first price to the last document. A two-person plumbing business replaces a water heater for a small dental office. Tax is left out to keep the numbers simple.
1. Quote Q-0058, sent October 1. Valid for 30 days.
| Line | Qty | Rate | Amount |
|---|---|---|---|
| 50-gallon water heater, supplied | 1 | $1,150.00 | $1,150.00 |
| Labor: remove old unit, install and test | 4 hours | $95.00 | $380.00 |
| Haul away old unit | 1 | $60.00 | $60.00 |
| Total | $1,590.00 |
2. The client accepts on October 3. The office manager replies by email: "Approved, go ahead Thursday."
3. Proforma PF-0058, sent October 3. The practice owner signs off any spend over $1,000 against an invoice-format document, so the plumber sends a proforma with the same lines and total, marked "Proforma invoice. Payment in advance not required." This step is optional. Most clients go straight from quote to invoice.
4. The job, October 8. During the install, the plumber finds a corroded shut-off valve. The office manager agrees by text to replace it for one extra hour of labor plus a $40 valve.
5. Invoice INV-0213, sent October 8. Due on October 22 (net 14).
| Line | Qty | Rate | Amount |
|---|---|---|---|
| 50-gallon water heater, supplied | 1 | $1,150.00 | $1,150.00 |
| Labor: remove old unit, install and test | 4 hours | $95.00 | $380.00 |
| Haul away old unit | 1 | $60.00 | $60.00 |
| Extra work agreed October 8: replace shut-off valve, labor | 1 hour | $95.00 | $95.00 |
| Shut-off valve, supplied | 1 | $40.00 | $40.00 |
| Total due | $1,725.00 |
The invoice notes "As per quote Q-0058, plus agreed extra work." The client can see why the total differs from the quote.
6. Payment on October 20. The office pays $1,725.00 by card from the invoice's pay link.
7. Receipt, sent October 20. "Received $1,725.00 by card on October 20, 2026, in full payment of invoice INV-0213. Thank you."
8. Credit note CN-0007, if something changes. Say the office later points out that their landlord removed the old unit, so the haul-away never happened. The plumber issues CN-0007 for -$60.00 against INV-0213 and refunds the $60 or holds it against the next job. The original invoice stays unchanged.
One job produced five documents, and each one had a different reader in mind: the quote for the decision, the proforma for the approver, the invoice for accounts payable, the receipt for the client's records, and the credit note for the correction. Our guide on how to write an invoice covers every field on INV-0213 in detail, and the invoicing for plumbers page has a full sample plumbing invoice.
If a job starts with a deposit, the same chain gets one extra invoice at the start. Our guide on how to invoice a deposit shows both ways to bill a deposit and the balance.
What is a credit note, and when do you need one?
A credit note reduces or cancels an invoice you already sent. It quotes the original invoice number and shows a negative amount. You issue one when you overcharged, when part of the job was cancelled, or when you agreed on a discount after invoicing.
Editing or deleting the original invoice breaks your record of what you billed, and the client may already have it filed. A credit note leaves both records intact and shows why the balance changed. Credit notes usually get their own number sequence, such as CN-0007, so they never clash with invoice numbers. When you undercharged instead, a debit note works the same way in the other direction.
How does SolidInvoice handle quotes, invoices and payments?
SolidInvoice keeps quotes and invoices for each client in one place. When a client accepts a quote, you mark it accepted and SolidInvoice creates a draft invoice with every line copied over, so nothing is retyped. Each invoice has a pay link for card or PayPal, payments are recorded against the invoice, and its status shows whether it is unpaid, partly paid or paid. If the client paid a deposit, the pay link charges only the remaining balance. See the features page or pricing for what each plan includes.
Quote vs invoice vs receipt FAQ
What is the difference between an invoice and a receipt?
An invoice asks the client to pay and states the amount and the due date. A receipt confirms the payment arrived and shows the amount, the date and the payment method. You send the invoice after the work and the receipt after the payment.
Is a quote the same as an invoice?
No. A quote offers a price before the work starts and does not ask for payment. An invoice asks for payment after the work is done. Once the client accepts a quote, the invoice normally uses the same prices, plus any extra work the client agreed to.
Is a quote legally binding?
An accepted quote can become part of a binding agreement, while an estimate is a best guess that can change. In England, Citizens Advice says a trader can't charge more than the quote without a good reason, such as extra work the customer agreed to. Rules vary by state and country, so check your contract.
What is the difference between a proforma invoice and an invoice?
A proforma invoice is a preview of the final invoice, sent before the work or delivery so the client can approve the spend or pay in advance. It is not recorded as a sale. The invoice is the final bill that the client pays against and that you keep for tax.
Can an invoice be used as a receipt?
Yes, once it is paid. Mark the invoice "Paid" and add the payment date and method, then send it back to the client. Send a separate receipt if the client asks for one or paid in cash.
Do I need to give a customer a receipt?
Send one when the customer asks or pays in cash. Card and bank payments leave a record on both sides, but some clients still need a receipt for their own books. Some places require receipts for certain sales, so check the rules where you work.
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