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How to Choose the Right Payment Terms

Payment terms are one of the most overlooked levers in a small business. Changing from Net 30 to Net 14 across your invoices reduces your average collection time by 16 days — without any other change to your business. For a business invoicing £10,000 per month, that's roughly £5,000 more in working capital at any given time.

The right payment terms depend on your client relationships, your invoice volume, and how much cash flow risk you can absorb. Here is how to think through the decision.

Net 30 vs Net 14: The Cash Flow Difference

Most freelancers and small agencies default to Net 30 because it's industry standard. But industry standard is not the same as the right choice for your business. Net 30 works for large corporations because they have AR teams, lines of credit, and the cash reserves to absorb 30-day collection cycles. Small businesses typically don't.

Net 14 is better for most freelancers and small businesses for three reasons: (1) you identify payment problems 16 days earlier, when the debt is fresh and the client is still engaged with the recent project; (2) your average days outstanding (DSO) improves, which directly improves cash flow; (3) clients who are going to pay late show up sooner in your AR aging, before the invoice ages into the 61–90 day bucket where recovery rates drop significantly.

Most clients accept Net 14 without negotiation. It's a professional standard — not aggressive. If a client insists on Net 30, that's usually fine. If they request Net 60 or Net 90, ask why. Genuine corporate payment cycles are a valid reason; general preference is not.

How Payment Terms Affect Your Cash Flow

Payment terms create a direct relationship between your revenue and your cash flow. If you invoice £10,000 on Net 30 terms, that £10,000 is not available to you for at least 30 days — and realistically 35–45 days if the client pays slightly late (as most do). That gap between earning money and receiving it is funded either by your cash reserves or your credit facility.

The formula: cash flow gap = average invoice amount × (payment terms + average days late). If you average £5,000 per invoice, Net 30 terms, and clients pay on average 10 days late — your cash flow gap is £5,000 × 40 days = roughly £6,700 per invoice in cash that's "out in the world" at any time. Shortening terms to Net 14 and tightening follow-up to reduce average lateness to 5 days reduces this to £5,000 × 19 days = £2,600. That's a meaningful difference in working capital.

How to State Payment Terms on an Invoice

Always state an explicit due date — not just the terms. "Net 30" is less clear than "Payment due by 15 March 2026." Including both is best: "Net 30 — payment due by 15 March 2026." This leaves no ambiguity and removes the need for the client to calculate the due date themselves.

The payment terms section of your invoice should also include: accepted payment methods (bank transfer, card, etc.), full payment details (bank account, sort code, SWIFT/BIC for international clients), a reference number the client should use, and your late fee clause if applicable. The less friction between reading the invoice and completing payment, the faster you get paid. For the exact wording to use, see the invoice wording guide.

When to Negotiate Payment Terms

The best time to negotiate payment terms is at project start, not after delivery. Once you've delivered the work, your leverage decreases — the client has what they wanted. Negotiate terms as part of the contract discussion, the same way you negotiate rate and scope.

If a large corporate client requires Net 60 or Net 90 terms, three options: (1) accept but factor the extended terms into your rate — essentially charging a premium for the credit you're extending; (2) require a deposit upfront to reduce your maximum exposure; (3) use invoice factoring to sell the receivable for 80–90% of face value and receive payment immediately. For most freelancers and small agencies, option (1) or (2) is most practical.

Legal Default Terms When None Are Stated

If you don't state payment terms, the law provides defaults — but they vary by jurisdiction:

• UK (B2B): 30 days from invoice date under the Net 30 convention, codified by the Late Payment of Commercial Debts Act 1998
• EU (B2B): 30 days under the Late Payment Directive (2011/7/EU)
• USA: "reasonable time" — courts typically interpret this as 30 days, but it varies by state
• Australia: "reasonable time" — typically 30 days

Relying on legal defaults is a bad practice. Always state your payment terms explicitly on every invoice to avoid ambiguity. Use the calculator above to generate the exact due date for any terms you choose, and include that date directly on the invoice.