What payment terms should I put on my invoice?
The short answer
Fourteen or thirty days. Agree the length with your client before the work starts, then write the due date on every invoice as a date, not just 'net 14'. The late payment law starts interest the day after a date you and the client agreed4, and a date that first appears on the invoice is usually not one. With no agreed date, payment is late 30 days after2 they get your invoice or you finish the work, whichever is later.
England and Wales only. WolfX is software, not a law firm.
What you can add
A £10,000 project, paid in three parts
Say you agree a £10,000 website build with another business on Monday 12 October 2026. The quote they accept by email sets three payments. The deposit is due on 19 October, before work starts. Each later invoice is due 14 days after it is sent, and shows its due date.
By 23 November, £7,000 of the £10,000 is due, with two weeks of the build still to go. One invoice on delivery with 30 days to pay would not fall due until 6 January 2027: 86 days after the quote was accepted.
The road ahead
Six steps. All free.
Step 1: Pick the length
Your terms are yours to set1. A small repair or weekly clean: due on receipt, or 7 days. A one-off project: 14 days, with stages. A retainer for a client with a payment run: 30 days.
'End of month plus 30' is not 30 days: on an invoice dated 1 October it falls due on 30 November, 60 days later. Shorter pays sooner; longer is an easier yes, and you fund the wait.
Step 2: Check it sits inside the limits
Count the days from the later of the day you finish and the day they get your invoice4. Between businesses, interest starts after day 604 even if you agree a later date. A later date holds only if it is not grossly unfair to you.
For a council or other public authority, interest starts after day 304 however late the agreed date, with no fairness test. Pushed for longer? See 60 or 90 days.
Step 3: Write the due date as a date
Write 'Due 16 November 2026', not 'net 14'. 'Net 14' doesn't say 14 days from what: the invoice date, the day they got it, or the day you finished. A date leaves nothing to count.
Step 4: Stage anything that takes weeks
Take a deposit, then stage payments, each due after the work it pays for. A payment due after its work is not an advance payment5, so its agreed date counts4.
A deposit tied to no part of the work is an advance payment5. If it is late, interest on it starts only the day after the whole job is done4, so make paying it the condition for starting.
Step 5: Add one line on late payment
Put the interest (8% over the Bank of England base rate6) and the fixed sum in your terms and on every invoice. The words are on their own page.
Step 6: Get the yes before you start
Email the letter below with the quote and ask for a reply. A yes by email gives you a dated record. A spoken yes can count too, but it is harder to prove.
Expect a yes, a question or a different date. Settle it before the work starts, then the invoice only repeats what they agreed.
A letter you can copy
Quote email with your payment terms
Send it with every quote, before any work starts. The reply is what makes the terms agreed, so wait for it.
Tap a highlighted gap to see what goes in it.
Send it by email with the quote attached, so it is dated, and keep their reply with the quote. For a small job, delete the deposit and stages lines and keep the rest. If they send their own terms back, settle the difference by email before you start.
When not to bother
When it isn't worth it
- You're selling to a consumer. The Act covers contracts between businesses3, so a sale to a householder follows other rules that this page doesn't cover.
- A big client sends its own terms. Get your date onto their purchase order first. Bend for work worth the wait, and price the wait: at the law's late rate of 11.75% (3.75% Bank Rate7 plus 8%), 60 days not 14 on £10,000 is £148.08.
- It is a small job. Stages on a £300 repair cost more admin than they save. One invoice with a due date 7 days out is enough.
- Your signed contract already names a date. Put that date on the invoice. A different one printed there is not the date you agreed4.
The Wolf's note
The date on an invoice is only as strong as the yes behind it. Get the yes while the client is still choosing you, in an email. After that, the invoice only repeats what they said.
Mr. Wolf · the AI inside WolfX
What comes next
Your next move
When it first goes quiet
When is an invoice officially late?
An invoice is late the day after the agreed date.
5 min read · Letter included
When it first goes quiet
Can a big company make me wait 60 or 90 days to be paid?
Up to 60 days. With a business, a longer date is not banned, but it holds only if it is not grossly unfair to you; otherwise interest starts on day 61.
5 min read · Letter included
Should I ask for a deposit or payment upfront, and how do I ask?
Yes, when a job costs you money before the client pays, or the client is new.
7 min read · Letter included
Don't want to do this yourself?
The Wolf does every step for you. He works out the sums, writes the letters and keeps track of every date. Nothing goes without your yes.