Whatever Date You Put On The Invoice, You Get Paid About Two Weeks After It

Every seasonal contractor knows the shape of the problem. Fuel, salt, parts, and payroll go out weekly. The money comes back in lumps, weeks after the work, and the gap between those two facts is the whole reason a profitable season can still leave you short in February.

The usual advice is to tighten your payment terms. It is good advice, but not for the reason it is normally given, and the difference matters when you are deciding what to change.

Billbooks published our own aggregated records: 53,095 paid invoices from 180 small businesses, issued between 2007 and August 2026. It is public, under a Creative Commons licence, and the raw file is downloadable. None of what follows has to be taken on trust.

Here is the number that reframes the problem. Due on receipt invoices were paid in 15.9 days on average. 

• Net 7 invoices in 18.6 days
• Net 15 invoices in 26.9 days.
• Net 30 invoices in 47.2 days.

Subtract the deadline from each and you get the interesting column. Due on receipt runs 15.9 days past due. Net 7 runs 11.6 days past. Net 15 runs 11.9. Net 30 runs 17.2.

Whatever date you write on the invoice, you are paid roughly twelve to seventeen days after it. The slip is remarkably stable. It does not care what the terms say.

The deadline is not a lever on whether you get paid. It is a lever on when.

Longer terms do not buy better behaviour either. The share of invoices paid by the due date was 39.1 percent on due on receipt, 48.5 percent on Net 7, 47.1 percent on Net 15 and 42.3 percent on Net 30. Four numbers inside a nine-point band, with no reward for generosity anywhere in it. Roughly 4 to 5 invoices in 10 arrive on time. Thirty extra days doesn't improve that.

The deadline is not a lever on whether you get paid. It is a lever on when. That is still worth pulling, and it is worth knowing which of the following four actually move money.

Shorten the Term & Know What You Bought

Moving from Net 30 to Net 7 does not fix the slip. It moves the whole curve forward: 18.6 days instead of 47.2, which is 28.6 days of cash. You are not asking anyone to behave differently. You are declining to finance them for a month. Net 7 also carried the highest on-time rate of the four. The fear that shorter terms annoy clients into paying later is not visible in this data.

Put a Real Date on It

Due on receipt had the worst on-time rate of any term tested, at 39.1%. That looks backwards until you say it out loud. "Due on receipt" is not a date. It is a sentiment. There is nothing for a bookkeeper to key into an accounts payable run and nothing to be late against, so it ends up in the pile with everything else. "Due 30 September" is a date. Write the date.

Make Sure it was Opened

This is the cheapest thing on the list, and it requires no negotiation with anybody. In our data, invoices that the client actually opened were paid in 19.3 days. Invoices never opened were paid in 26.2 days. Just under 7 days of float, sitting in whether your invoice reached a human.

For a contractor, that usually means the invoice is going to the address of the person who hired you rather than the person who pays you, or into an office inbox nobody monitors in the middle of a storm week. Ask once, at quoting, who processes invoices and where they want it sent. Then check that it landed, rather than assuming silence is progress.

A penalty that is never applied is not a deterrent; it is decoration.

The Clause You Never Switched On

A late fee was set on zero of 67,634 invoices in our data. Not a handful. None.

Almost every service agreement I have read carries an interest clause for overdue accounts. Practically nobody turns it on. If you are going to keep it in the contract, decide now what the trigger is and who sends it, because a penalty that is never applied is not a deterrent; it is decoration. If you are not going to enforce it, at least stop believing it is protecting you.

Honesty requires one caveat here: because nobody in the sample used late fees, this data cannot tell you whether they work. It can only tell you they are not being used.

What the Data Does Not Cover & what I Would Still Do

The study measures terms and timing, not billing frequency, so treat the following as one operator's opinion rather than a finding. 

In seasonal work, the compression is the enemy. Billing monthly in January means one invoice covering six visits, landing on a Net 30 term, paid in mid to late February, against costs you paid weekly. Billing per visit, or every fortnight, makes each invoice smaller, easier to approve without a conversation, and starts the clock 6 times instead of once. Deposits on contracts signed before the season do the same job at the other end.

The One Thing Worth Doing Right Away

Open your books and work out your own version of the number above. Take your last 30 paid invoices, and for each one subtract the due date from the date the money arrived. The average is your slip. 

If it is around two weeks, you are normal, and the question is which of the four levers above you are not using. If it is materially worse, you do not have a terms problem; you have a specific client problem. Now you know which one.

The invoice payment study is published at billbooks.com/invoice-payment-study under CC BY 4.0, with the full dataset downloadable.