The short answer
- Before the work: a quote (or an estimate). It tells the client what you’ll do and for how much. Once accepted, a quote is a fixed price.
- After the work: an invoice. It asks for payment for what you’ve delivered. Send it as soon as the job is done.
- A quote is a fixed price; an estimate is a best guess. In the UK, Citizens Advice says a trader can’t charge more than a quote without a good reason, but can go over an estimate within reason.
- Deposits sit in between. Ask for them on the quote, and invoice them when you take them. In the UK, if you’re VAT-registered, a deposit usually creates its own tax point.
- Never send an invoice to “give a price”, and never treat a signed quote as an invoice.
Two documents, two moments
Quotes and invoices often look alike: same lines, same prices, same template. But they arrive at different times and do different jobs.
| Quote | Invoice | |
|---|---|---|
| When | Before the work starts | As soon as the work or delivery is done |
| Purpose | Offer a price and a scope | Request payment and record the sale |
| What it becomes | Part of the contract once accepted | Your record of income; the client’s record of the expense |
| Numbering | Recommended | Unique and sequential |
| Tax | Shown for information | The basis for the VAT or sales tax you account for |
| Can you change it? | Yes, with a revised quote, until accepted | Don’t edit it: issue a credit note and a new invoice |
When
QuoteBefore the work starts
InvoiceAs soon as the work or delivery is done
Purpose
QuoteOffer a price and a scope
InvoiceRequest payment and record the sale
What it becomes
QuotePart of the contract once accepted
InvoiceYour record of income; the client’s record of the expense
Numbering
QuoteRecommended
InvoiceUnique and sequential
Tax
QuoteShown for information
InvoiceThe basis for the VAT or sales tax you account for
Can you change it?
QuoteYes, with a revised quote, until accepted
InvoiceDon’t edit it: issue a credit note and a new invoice
A quote exists to prevent surprises. An invoice exists to get you paid. Most disputes over price come from mixing the two up.
Quote, estimate, bid: the words matter
In everyday speech people use these interchangeably. For a customer dispute, they don’t mean the same thing.
- Quote (quotation): a firm price for a defined job. Citizens Advice describes it as a promise to do the work at an agreed price. The trader can’t charge more unless there’s a good reason, for example the client agreed to extra work, or the price was an obvious mistake.
- Estimate: your best guess at the cost. You can charge more, but only within reason.
- No price agreed at all: under the UK’s Consumer Rights Act 2015, the consumer only has to pay a reasonable price.
In the US there’s no single national rule, but some states regulate estimates in specific trades. California is a good example: under its Business and Professions Code, an automotive repair dealer must give a written estimate for parts and labour, can’t start work or charge anything before the customer authorises it, and can’t charge more than the estimate without the customer’s consent, obtained before the extra work is done. If you work in a regulated trade, check your state’s rules.
The practical takeaway: call the document what it is. If you’re confident of the price, send a quote. If you genuinely can’t know until you start, send an estimate and say what could change it.
When to send a quote
Send a quote whenever the price isn’t obvious to the client before you start: custom work, building and repair jobs, multi-day projects, anything priced on what you find on site.
You don’t need one for every sale. If your price is published (a haircut, a one-hour lesson at a listed rate), the client already knows it, and an invoice or receipt after the work is enough.
Three habits that help:
- Give it an expiry date. “Valid for 30 days” protects you if material prices move.
- Get acceptance in writing. A signature, an online “accept” click or a written reply. Without it, you have an offer, not an agreement.
- Number your quotes. It’s the only way to know which version the client accepted. Use a separate series from your invoices (Q-2026-021 for quotes, INV-2026-058 for invoices).
Our guide to writing a quote has a full template and covers what to include.
When to send the invoice
As soon as the job is done or the goods are delivered. There are three reasons not to wait:
- Payment terms run from the invoice. In the UK, if no terms were agreed between businesses, payment is due 30 days after the customer receives the invoice or the goods or services, whichever is later. Every day you wait to invoice is a day added before you’re paid.
- VAT deadlines. If you’re VAT-registered in the UK, you must issue a VAT invoice within 30 days of the date of supply.
- You can’t chase what you haven’t billed. Our guide to chasing an unpaid invoice starts from a dated invoice with a clear due date.
For regular work with the same client (weekly cleaning, monthly maintenance, retainer hours), one invoice per month listing each visit is common and perfectly fine, as long as your terms say so.
In between: deposits, proformas and extra work
Deposits. For bigger jobs, ask for a deposit on the quote (“30% on acceptance”), then invoice it when you take it. The final invoice shows the full price, deducts the deposit already invoiced and asks for the balance. In the UK, VAT-registered businesses should note HMRC’s rule: for an advance payment, the tax point is the date you issue a VAT invoice for it or the date you receive the payment, whichever happens first.
Proforma invoices. A proforma looks like an invoice but is really an offer, often used for customs or for a client’s internal approval before paying upfront. It doesn’t replace the accepted quote or the final invoice. See our proforma invoice guide.
Extra work. If the job turns up something unplanned, don’t just add it to the invoice. Quote it separately and get it accepted first. An invoice should only contain what the client agreed to.
Worked example: from quote to final invoice
Aisha is a web developer in Manchester, not VAT-registered, building a site for a local bakery.
- Quote, 1 September: design and build £1,500, copywriting 6 hours at £45 = £270, total £1,770. Valid 30 days, 40% deposit on acceptance.
- Acceptance, 3 September: the owner accepts the quote online.
- Deposit invoice, 3 September: 40% of £1,770 = £708.
- Final invoice, 24 September, the day the site goes live: total £1,770, less deposit invoiced £708, balance due £1,062, payable within 14 days.
Check: £708 + £1,062 = £1,770. The client pays exactly the quoted price, and every payment matches an invoice.
Mistakes that cause disputes
- Sending an invoice to “give a price”. An invoice uses up a number in your sequence and, if you’re VAT-registered, can trigger VAT. If the client says no, you’ll need a credit note. To propose a price, send a quote.
- Treating the accepted quote as the invoice. The quote proves the agreed price, not that the work was done or that payment is due. You still need an invoice.
- Billing more than the quote without agreement. Unless there’s a good reason, like extra work the client approved, you can’t charge more than a quote.
- Taking a deposit without paperwork. Invoice or receipt every deposit, or the final invoice becomes confusing for both sides.
- Waiting to invoice. Payment terms only start once the invoice lands.
From quote to invoice without retyping
The slowest part is often copying the quote into the invoice. In Binome360, you say or type the quote in one sentence; the client reads it, downloads a PDF and accepts it online from a link; the accepted quote becomes an invoice in one tap, with the same lines and its own numbering.
The bakery site is live, invoice the balance on quote Q-2026-021
Ready: invoice INV-2026-058 for Crumb & Co, from quote Q-2026-021: total £1,770.00, deposit of £708.00 deducted, balance £1,062.00 due in 14 days. Save it? You can then send it as a link.
Your assistant prepares the invoice; you check it, then send it.
Try Binome360 for freeBinome360 prepares clear quotes and invoices; it isn’t a certified e-invoicing platform and doesn’t process payments.
Frequently asked questions
Is a quote legally binding?
Once the client accepts it, a quote generally forms part of your agreement: you’ve committed to the price and scope, and they’ve committed to pay it. Before acceptance, it’s an offer you can withdraw or revise. In the UK, Citizens Advice says a trader can’t charge more than a quote without a good reason.
Can I send an invoice without a quote?
Yes. Quotes are optional in most situations. For a small job at a known price, an invoice after the work is enough. Without a quote, though, you have nothing in writing to point to if the client later disputes the price.
What’s the difference between a quote and an estimate?
A quote is a fixed price for a defined job. An estimate is your best guess, which can go up within reason. If you’re not sure of the final cost, call it an estimate and explain what could change it.
Should quotes and invoices use the same number sequence?
No. Keep them separate. Invoices need a unique, unbroken sequence; quotes don’t, and many never turn into invoices. Mixing them leaves gaps in your invoice numbering.
How soon after finishing should I send the invoice?
The same day if you can. If you’re VAT-registered in the UK, you must issue a VAT invoice within 30 days of the supply, but waiting that long only delays your payment.
In short
Send a quote before the work to fix the price, a deposit invoice if you take money upfront, and a final invoice as soon as the job is done. Call estimates estimates, get acceptance in writing, and never bill beyond the quote without agreement. First action: for your next job, send the quote the same day you see the client, with an expiry date and the deposit terms spelled out.
Sources
- Citizens Advice, “Problem with building work, decorating or home improvements” (quotes, estimates and reasonable price): citizensadvice.org.uk.
- Consumer Rights Act 2015, section 51 (reasonable price where none is agreed): legislation.gov.uk/ukpga/2015/15/section/51.
- California Business and Professions Code, section 9884.9 (written estimates for automotive repair): law.justia.com.
- HMRC, “VAT guide (VAT Notice 700)”, section 14 (deposits and advance payments): gov.uk/guidance/vat-guide-notice-700.
- HMRC, “Record keeping for VAT (VAT Notice 700/21)”, section 3.1 (issuing VAT invoices within 30 days): gov.uk/guidance/record-keeping-for-vat-notice-70021.
- GOV.UK, “Late commercial payments: charging interest and debt recovery” (default 30-day payment term): gov.uk/late-commercial-payments-interest-debt-recovery.
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