What Is Net 45? Payment Terms Explained

Net 45 asks for the full invoice amount within 45 days. That sits between two numbers the law already uses. Thirty days is the period several late-payment laws apply when a contract fixes no date at all, and 60 days is the line European and UK law draw for terms that businesses agree between themselves. Net 45 is inside that band, which is why it raises fewer legal questions than Net 60 or Net 90, until the buyer is a public body or the 45 days are business days.

This guide is mostly about those two cases: what EU, UK and US federal rules do to Net 45 when a public authority is paying, and why "45 business days" lands past the 60-day line. The guides on Net 30 and Net 60 cover the terms on either side.

What Net 45 means

The buyer owes the whole invoice, undiscounted, 45 days after the start date. An invoice dated Wednesday, April 1, 2026 on Net 45 terms reaches day 45 on Saturday, May 16, 2026.

That example already shows the two questions the term leaves open. It does not say whether the 45 days are calendar days or business days, and it does not say what happens when day 45 is a Saturday. The contract answers both, and where it is silent, the law of the contract does.

Net 45 with a public-sector buyer

Between businesses, 45 agreed days sit comfortably inside the 60-day rules that the Net 60 guide quotes. A public buyer changes that, because for public authorities the statutory starting point is 30 days.

EU. Article 4 of Directive 2011/7/EU sets 30 calendar days as the period for a public authority, allows a longer agreed period only if it is expressly agreed and objectively justified by the nature or features of the contract, and caps it at 60 days in any event. Net 45 with a public authority therefore needs that express agreement and that objective justification.

UK. Section 4(2D) of the Late Payment of Commercial Debts (Interest) Act 1998 makes the last day of the relevant 30-day period the relevant day for a public-authority purchaser whenever the agreed payment day falls later. Statutory interest can then start the day after that 30-day period ends, although Net 45 was agreed.

US federal contracts. FAR 32.904(b) dates payment on the later of the 30th day after the designated billing office receives a proper invoice and the 30th day after Government acceptance, unless one of its listed exceptions applies. A supplier's own Net 45 does not lengthen that.

Forty-five business days

The laws in this guide count calendar days, and this site's calculators read a bare "Net 45" as 45 of them. Forty-five business days are a different term. On a Monday-to-Friday week they are nine working weeks: 63 days on the calendar counted from a working day before any holiday, and more with one. Counted from April 1, 2026, the 45th business day is June 4 in the US calendar (64 calendar days, Memorial Day included), June 5 in Spain's national calendar (65) and June 9 in the England and Wales calendar (69, with Good Friday, Easter Monday and two May bank holidays). The invoice due date calculator dates either reading: pick Net 45 for calendar days, or Custom with business days for the other.

Each of those dates is past day 60, so a business-day Net 45 is subject to the tests in the Net 60 guide: in the EU it stands only if expressly agreed and not grossly unfair to the creditor, in the UK statutory interest can run from the end of the 60-day period, and in Spain Ley 3/2004 does not allow an agreed term beyond 60 calendar days at all (article 4.3).

When the 45 days start

The term on an invoice usually counts from the invoice date, but the contract can name another start: delivery, receipt of the goods, completion of the service, or acceptance after an inspection. On a shipment that takes a week to arrive, "45 days from receipt of goods" and "45 days from invoice date" are a week apart. When the contract names no payment date at all, the EU Directive, the UK Act and FAR 32.904 fall back to 30 days counted from receipt, as the Net 30 guide sets out.

Day 45 on a Saturday

In the April 1 example day 45 is Saturday, May 16, 2026, and the US, UK, German and Spanish calendars of the invoice due date calculator all give Monday, May 18 as the next business day. Net 45 itself does not make the Monday payment on time. The cleanest contracts say so in a sentence such as "payment due on the next business day if the due date is not a business day"; US federal contracts have that rule already, in FAR 52.232-25.

What the extra 15 days cost the supplier

Moving a customer from Net 30 to Net 45 extends the supplier's financing of each invoice by 15 days. On a 10,000 invoice, at a 10 percent annual cost of money, those 15 days cost 10,000 x 0.10 x 15 / 365, about 41. Across a whole ledger the receivables balance grows in proportion: half a month more of sales outstanding when every invoice is paid on time. The days sales outstanding guide shows how to measure the days your customers actually take, which can differ from the 45 days written on the invoice.

Writing a Net 45 term that leaves no gap

Three things make a Net 45 term unambiguous. Name the start date ("45 calendar days from the invoice date" or "from delivery"), name the counting method, and name the weekend rule. If you offer a discount for early payment, write it as a separate term, such as "2/10 Net 45"; the early payment discount calculator converts any such discount into an annual rate. If a payment arrives late, the late payment interest calculator works out what is owed.

FAQ

Does Net 45 mean 45 business days or 45 calendar days?

Calendar days, unless the contract says otherwise; that is how the late-payment laws count and how this site's calculators read the term. On a Monday-to-Friday week, forty-five business days take 63 calendar days counted from a working day and never fewer than 61, which is past the 60-day line, so a contract that means them should spell it out.

When does the 45-day period start?

From whatever the contract names: the invoice date, delivery, receipt of goods, completion or acceptance. A contract that names no payment date gets the statutory fallback of 30 days from receipt instead.

Is Net 45 allowed under late-payment law?

Between businesses, as calendar days, yes: 45 days is inside the 60-day line of Article 3(5) of Directive 2011/7/EU and section 4(2E) of the UK Late Payment Act, which test agreed terms only beyond 60 days, and inside the 60 calendar days Spain's Ley 3/2004 allows by agreement (article 4.3). Read as 45 business days, the term passes 60 calendar days, and Spain does not allow it.

Does Net 45 work with a public-sector buyer?

Not as freely. Article 4 of the EU Directive sets 30 calendar days for public authorities and allows longer only when expressly agreed and objectively justified, never beyond 60. Under section 4(2D) of the UK Act, statutory interest on a debt owed by a public authority can start the day after the 30-day period ends, even when Net 45 was agreed. US federal contracts follow FAR 32.904's 30th-day rule unless one of its exceptions applies.

What happens if a Net 45 due date falls on a weekend or holiday?

Nothing, unless the contract or the governing law says so. On an invoice dated April 1, 2026 day 45 is Saturday, May 16; a contract clause, or FAR 52.232-25 on a US federal contract, is what makes payment on Monday, May 18 timely.