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Best Invoice Payment Terms for Freelancers
Net 15 vs Net 30 vs Net 60 — The Full Breakdown

By Santanu Sarma — Mathematical Economics & Public Finance · Updated June 2026 · 10 min read

You've just signed a contract that feels like a genuine breakthrough. Solid rate. Interesting work. A client with a real brand and a proper procurement process. Then you hit page three.

Two words buried in the payment section: Net 60. Your rent is due in five days.

That sinking feeling isn't irrational panic. Payment terms are the single most overlooked variable in whether a freelance business actually survives. They're not accounting jargon — they determine when you can pay your own bills, whether you need a line of credit to cover a quiet month, and whether you can ever stop refreshing your bank account at midnight. This guide breaks down Net 15, Net 30, and Net 60 as real decisions with real cash consequences. You'll know exactly which to choose, when to push back, and what the numbers actually look like.

What Invoice Payment Terms Actually Mean

"Net X" means your client has X calendar days from the invoice date to pay the full amount. Net 30 = 30 days. Net 60 = 60 days. The "net" refers to the total amount due — no partial credit, no instalments implied.

The clock starts when you issue the invoice, not when the client's accounts payable team stamps it received, not when their manager approves it. Large companies will often claim the timer starts at their internal approval date — push back on this in your contract, explicitly.

Other terms you'll see: Due on Receipt (payment expected immediately), Net 7 (rare, used for very small transactions or trusted repeat clients), and 2/10 Net 30 — the client gets a 2% discount if they pay within 10 days instead of 30. That last one is more powerful than it looks, and we'll return to it.

Net 15 vs Net 30 vs Net 60: Head-to-Head Comparison

The table below covers the factors that actually matter for freelancers — not just what the term means, but who it suits, what it does to your cash flow and DSO, and where you'll typically encounter it in the wild.

What Days Sales Outstanding (DSO) Is Actually Telling You

DSO measures how long, on average, it takes to collect payment after completing work. If you're on Net 30 but clients typically pay on day 38, your real DSO is 38 — and that gap matters far more than the term on paper.

A low DSO means money moves fast. A high DSO means you're effectively lending your clients money, interest-free, for weeks at a time. When you have multiple clients all on Net 60, this creates a structural cash problem — not a one-off inconvenience.

How to calculate your own DSO

Take your total accounts receivable balance, divide by annual revenue, multiply by 365. If you have £6,000 outstanding and earn £72,000/year:

The AR Float: Why Net 60 Costs You More Than You Think

Accounts Receivable Float is the money you've earned but can't yet touch — it's sitting in your clients' accounts instead of yours. This isn't a hypothetical concern. It's a real, calculable figure that determines whether you can pay your own bills this month.

The formula:

Worked example — £8,000/month freelancer on Net 60

Say you're a freelance UX designer earning £8,000 per month (£96,000/year) and all your contracts run on Net 60 terms.

That £16,000 is gone from your operational reality. It's money you've earned, but you cannot pay your tax bill with it. You cannot put it toward equipment or training. You cannot use it as a buffer when a client goes quiet.

The switch from Net 60 to Net 15 frees up approximately £12,000 of working capital — just by changing two digits in your payment terms.

This is why your day rate must account for payment terms

If a client insists on Net 60, they are effectively receiving an interest-free loan of ~£16,000 from you at all times. A 5–10% premium on the day rate for long-payment-term contracts is entirely defensible — frame it as standard practice and most serious clients won't argue.

How to Choose the Right Term for Each Client

There's no single correct answer — the right term depends on who your client is, your own cash reserves, and the size of the project.

Use Net 15 when:

You're working with a small business or individual on a short-turnaround, discrete project. Also the right call when you're early in a relationship and want payment in hand before the next milestone begins. Pair it with a 50% deposit upfront to remove all cash flow risk.

Use Net 30 when:

This is your solid default for ongoing retainer clients and medium-sized agencies. It gives clients room to run their internal payment cycle while keeping your DSO reasonable. If you want faster payment without creating friction, offer a 2% discount for payment within 10 days — this costs you little and motivates fast action.

Accept Net 60 only when:

The contract value is high enough that the float cost is baked into your rate, or when the client is a large enterprise where Net 60 is genuinely non-negotiable in procurement policy. Never accept it as a default without running the AR Float formula above and adjusting your rate accordingly.

How to Negotiate Better Terms Without Losing the Client

Most freelancers accept whatever terms are in the contract because they're afraid to push back. The reality: clients expect negotiation. A polite, confident email asking to shift from Net 60 to Net 30 rarely kills a deal — it usually just gets accepted.

The split-the-difference approach

If a client offers Net 60, counter with Net 30. If they push back, offer Net 45. You've improved your position meaningfully and the client feels like they've won something. Everyone moves on.

Offer an early payment discount

A 2/10 Net 30 structure — "2% off if paid within 10 days, otherwise full amount due in 30 days" — works well with clients who have budget flexibility. On a £3,000 invoice, the client saves £60. You get paid 20 days earlier. It's a better deal for both sides than it looks.

Never negotiate terms after the invoice is sent

Lock in payment terms in the contract or project agreement, before work begins. Add one clear line to every proposal: "Payment terms: Net 15/30 from invoice date." Raising it after submission looks desperate and is far harder to enforce. Done upfront, it's just professional practice.

Late Payment Fees: The Clause That Changes Client Behaviour

A late fee clause doesn't just recover money — it shifts how clients prioritise your invoice. When they know that missing the due date triggers a 1.5% monthly charge, your invoice moves up the queue ahead of ones with no consequence for delay.

The standard structure is 1.5% per month (18% annually) on the outstanding balance, applied from the day after the due date. On a £2,000 invoice, that's £30 per month — not life-changing, but the signalling effect is what matters.

Display it plainly on every invoice: "Invoices unpaid after [due date] are subject to a 1.5% monthly late fee." You don't always have to enforce it — but having it there shifts the dynamic entirely.

You need to include this clause in your contract or engagement letter before work begins for it to be legally enforceable. Adding it to the invoice alone, after the fact, is significantly weaker in most jurisdictions.

Frequently Asked Questions

Further Reading & Resources

This article is informational and reflects general payment terms practice as of June 2026. It is not legal or financial advice. Late fee enforceability varies by jurisdiction — always confirm applicable rules with a qualified professional before including specific penalty clauses in client contracts.