Can a customer take an early-payment discount after the discount period?

Not under the plain terms. On 2/10 net 30, the 2% is offered only for payment within 10 days, so a reduction taken later was not earned. On federal contracts, 31 U.S.C. 3904 allows the reduced amount only when payment is made in time. On commercial work, the quote, the PO and the invoice decide; ask an attorney about a disputed amount.

What does 2/10 net 30 mean?

2% off the invoice if it is paid within 10 days; otherwise the full amount is due within 30 days. The terms should also say when the count starts. On federal contracts, FAR 52.232-8(b) counts from the date of the invoice.

How do you collect an unearned discount from a customer?

Send one short letter to accounts payable, copied to the buyer, listing the invoice numbers, invoice dates, payment dates and the amount deducted after the window, and ask for the difference with the next remittance or a written reason. If it keeps happening, move that account to plain net terms.

What is the annual cost of offering 2/10 net 30?

About 37% a year: 2 ÷ 98 × 365 ÷ 20. The customer gives up 2% to pay 20 days sooner. On 1/10 net 30 the same arithmetic gives about 18%.

When does the discount period start on an invoice?

Whenever the agreed terms say it does: the invoice date, receipt of the invoice or receipt of the goods. On federal contracts it is the invoice date, or the billing office’s annotated receipt date if the invoice is undated. Printing the invoice date and the last day of the window on the invoice removes the argument.

Answers · Machine shops

2/10 net 30, paid on day 50, short 2%: is the money still owed?

When a customer on 2/10 net 30 pays on day 50 and still deducts the 2% discount, the discount was not earned: the terms offer 2% off only for payment within 10 days, and the full amount was due by day 30. Whether a shop can collect the difference depends on the terms both sides actually agreed to — the quote, the purchase order, the invoice — and on federal work a clause and a statute spell it out. This guide covers what the terms promise, what a 2% early-payment term costs a shop in annual terms, a twelve-month remittance check that finds every late deduction, invoice-date discipline, and the one letter to send before moving a repeat account to plain net terms. It quotes federal rule text as it read on October 17, 2026. It is not legal advice.

By Tamara Stepanyan, founder of Lumina Business Advisory · Updated October 27, 2026 · Sources checked October 17, 2026 · Editorial standards

What 2/10 net 30 promises, and when the 2% is earned

The notation is two offers in one line. “2/10” means 2% off the invoice if payment arrives within 10 days. “Net 30” means the full amount is due within 30 days. A payment on day 12 owes the full invoice. A payment on day 50 owes the full invoice and is 20 days late.

The day the count starts is part of the terms. Commercial paper can count from the invoice date, from receipt of the invoice or from receipt of the goods, and the quote, the PO and the invoice do not always say the same thing. Federal contracts settle it in writing. FAR 52.232-8(b), Discounts for Prompt Payment: “In connection with any discount offered for prompt payment, time shall be computed from the date of the invoice.” If the contractor puts no date on the invoice, the period runs from the date the billing office receives a proper invoice, provided the agency annotates the receipt date. Payment counts as made on the date on the check or, for an electronic funds transfer, the specified payment date.

The statute behind the clause is blunter. Under 31 U.S.C. 3904, an agency offered a reduction for payment within a specified time “may pay the discounted amount only if payment is made within the specified time,” with the time determined from the date of the invoice, and it pays an interest penalty on an amount left unpaid in violation. The Prompt Payment clause, FAR 52.232-25(a)(6), says the payment office “will pay an interest penalty automatically, without request from the Contractor, if the Government takes a discount for prompt payment improperly.” The Treasury rule at 5 CFR 1315.7(b) says the same for a discount taken after the deadline.

Commercial customers have no equivalent federal rule. The answer sits in the documents: the terms printed on the quote, the terms on the customer’s purchase order, and the terms on the invoice. When the quote and the PO disagree, which terms govern is a battle-of-the-forms question under UCC § 2-207, and for a large amount it is a question for the shop’s attorney.

What the 2% costs a shop: the annual arithmetic

An early-payment term is a price cut traded for 20 days of credit. On 2/10 net 30, the customer who pays on day 10 instead of day 30 keeps $2 of every $100 and pays $98 twenty days sooner. Put on an annual basis, that is 2 ÷ 98 × 365 ÷ 20, about 37%. On 1/10 net 30 it is 1 ÷ 99 × 365 ÷ 20, about 18%.

That arithmetic is why a buyer with cash takes every early-payment term on offer, and why it is expensive money for a job shop to hand out. It makes sense when the shop needs cash faster than any line of credit would supply it, and when the customer really pays on day 10. A customer who pays on day 50 and still deducts 2% has turned the trade into a price cut plus 50 days of credit at no cost.

Illustrative example: a customer is invoiced $40,000 a month on 2/10 net 30, pays around day 50 and deducts 2% each time. That is $800 a month, $9,600 a year, in reductions the terms did not grant, on top of payments 20 days past the net date. The figures are invented for the example; the remittance check below finds the real ones.

The remittance check: twelve months in one afternoon

The accounting system already holds everything needed: invoices with their dates and terms, and payments with their dates and amounts. The check takes an afternoon with an export open:

Export twelve months of customer payments, with the invoice numbers each payment was applied to
Keep the payments where the amount paid is less than the invoice total and the short amount matches the early-payment percentage
For each one, count the days from the invoice date (or whatever start date the terms name) to the payment date: the check date, or the settlement date for an ACH or wire
Flag every reduction taken after the window: day 11 or later on 2/10 net 30
Total the flagged amounts by customer, and note each customer’s average days to pay
Set aside short payments with other reasons — a rejected part, a freight dispute, a price difference — so nothing is counted twice

The result is a short list: customer, number of late reductions, total dollars, average days to pay. It is also the list to bring to each customer, invoice by invoice, so the conversation is about dates rather than about trust.

Invoice-date discipline: the window starts with the invoice

On terms that count from the invoice date, an invoice that leaves late gives the customer a later window. A part shipped on the 3rd and invoiced on the 12th, after the certs were found and the portal upload went through, starts its 10 days on the 12th. Nine days of credit went out the door with the parts.

Three habits keep the date clean:

Invoice on the ship date, with the certs, certificate of conformance or inspection report the PO asks for in the same package
Print the invoice date and the terms on the invoice, and spell out the last day of the early-payment window in plain words
Record the date the invoice reached the customer — the portal confirmation, the sent email — so a disputed window has evidence behind it

On federal work, FAR 52.232-8(b) falls back to the billing office’s receipt date when the invoice carries no date. A dated invoice keeps the clock where the shop put it.

One letter, then plain net terms

A late reduction can be a payables-system setting rather than a decision anyone made, so the first contact assumes that. The letter is short: the invoice numbers, the invoice dates, the payment dates, the amount deducted after the window, and one request — add the difference to the next remittance, or say in writing why it was taken. It goes to accounts payable with a copy to the buyer, who is the person that wants the next job to go smoothly.

If the pattern continues, the decision is commercial rather than legal: take the early-payment term off that customer’s quotes and invoices and move the account to plain net terms, or price the cost of slow payment into the quote. Before rebilling or writing anything that reads like a demand, read what the quote and the PO actually say, and ask the shop’s attorney when the amount is large.

There is a quieter option too: stop offering early-payment terms to customers who do not need them. A shop that offers 2/10 net 30 pays an annual rate near 37% to every customer who takes it on time, and gets nothing at all from the ones who take it late.

When not to chase it — and when not to hire anyone

Some late reductions are not worth a letter. A single one a day or two past the window, from a customer who otherwise pays on day 10, can cost less than the conversation. Write the threshold down — a number of days, a dollar amount — so the decision is made once and not argued invoice by invoice.

An outside review earns its fee when late reductions are one leak among several: invoices dated days after shipment, terms that drift from net 30 to net 60, revisions shipped at the old price, quotes with no recorded outcome. That is the work of a machine shop consultant who reads the records rather than the floor. Our Revenue Review reads the shop’s own invoices, payments, POs and shipping records, read-only, and puts a monthly dollar figure on each leak the records support. It takes two weeks. It never contacts a customer. We do not run a machine shop, and there are no client case studies on this site yet.

If the remittance check above finds a few hundred dollars a year, the shop has its answer at no cost. Book a free 20-minute call only if the numbers point somewhere.

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Asked right after

Can a customer take an early-payment discount after the discount period?: Not under the plain terms. On 2/10 net 30, the 2% is offered only for payment within 10 days, so a reduction taken later was not earned. On federal contracts, 31 U.S.C. 3904 allows the reduced amount only when payment is made in time. On commercial work, the quote, the PO and the invoice decide; ask an attorney about a disputed amount.
What does 2/10 net 30 mean?: 2% off the invoice if it is paid within 10 days; otherwise the full amount is due within 30 days. The terms should also say when the count starts. On federal contracts, FAR 52.232-8(b) counts from the date of the invoice.
How do you collect an unearned discount from a customer?: Send one short letter to accounts payable, copied to the buyer, listing the invoice numbers, invoice dates, payment dates and the amount deducted after the window, and ask for the difference with the next remittance or a written reason. If it keeps happening, move that account to plain net terms.
What is the annual cost of offering 2/10 net 30?: About 37% a year: 2 ÷ 98 × 365 ÷ 20. The customer gives up 2% to pay 20 days sooner. On 1/10 net 30 the same arithmetic gives about 18%.
Does the federal government pay interest if it takes a discount late?: Yes. FAR 52.232-25(a)(6) says the payment office pays an interest penalty automatically, without a request from the contractor, if the government takes a discount for prompt payment improperly, and 5 CFR 1315.7(b) applies the penalty to a discount taken after the deadline.
When does the discount period start on an invoice?: Whenever the agreed terms say it does: the invoice date, receipt of the invoice or receipt of the goods. On federal contracts it is the invoice date, or the billing office’s annotated receipt date if the invoice is undated. Printing the invoice date and the last day of the window on the invoice removes the argument.

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