For your business4 min read

How to write an invoice that gets paid on time

Invoices are simple documents but small details determine whether you're paid in 7 days or 60. Here's exactly what to include and what to leave off.

Quick answer

A proper invoice includes: your business name and contact details, the client's business name and contact, a unique invoice number, the issue date and payment due date, a clear description of work and amount, any tax (VAT/sales tax), the total amount due, and your bank or payment details. Use shorter payment terms (Net 14, not Net 30 or 'on receipt'), state the due date specifically, and automate reminders. Invoices that follow these basics get paid 30–50% faster than vague ones.

Step-by-step

Use invoicing software, not Word or Excel

Manual invoices in Word, Excel, or PDF are the biggest reason small businesses get paid late. No auto-reminders, no payment tracking, no professional appearance. Use a proper tool: Wave (free, US/Canada), FreeAgent (free for UK via Mettle), Stripe Invoicing (free if already on Stripe), or QuickBooks/Xero if you're past the simple stage. Setup takes 30 minutes; payback is months of saved time.

Include every required element

A complete invoice has: your business name, address, contact details, and trading number (UTR for UK sole traders; EIN for US LLCs); your client's business name and contact details; a unique invoice number (sequential — 001, 002, etc.); the issue date AND the payment due date; a clear description of services with quantities and rates; subtotal, tax (VAT in UK if registered, sales tax in some US states), and total; and your bank or payment details. Missing any of these gives clients reason to delay or query.

Use short payment terms

Industry default 'Net 30' was set for an era when invoices were mailed. In 2026, Net 14 should be your default and Net 7 is reasonable for established clients. State the specific due date ('Due by 25 June 2026') not just 'Net 14' — concrete dates feel more urgent. For new clients or large amounts, ask for 50% upfront and 50% on completion; this filters time-wasters and protects your cash flow.

Write a specific work description

Vague descriptions ('Consulting services') give clients excuses to query the invoice. Specific descriptions ('Strategy consulting — 4 sessions, 1–25 June 2026; Final strategy document delivered 23 June') leave no room for confusion. For project-based work, list deliverables and milestones; for hourly work, list dates and brief descriptions. Specificity reduces queries and gets you paid faster.

Make payment frictionless

Make it easy to pay you. Three things. Include bank details (account name, account number, sort code/routing number) directly on the invoice. Provide a card payment link (Stripe Invoicing, Square, etc.) — card-payable invoices get paid 30–50% faster. For UK invoices, include a 'Pay by bank transfer' instruction with all the details a client's accounts payable team needs. Don't make clients hunt for how to pay you.

Automate reminders

The single biggest reason invoices go unpaid: nobody reminds the client. Set up automatic reminders in your invoicing tool. Standard cadence: a polite reminder 3 days before due date, a firmer reminder 1 day after due date, and an escalation 7 days after. Most invoicing software (Wave, FreeAgent, Stripe, QuickBooks) handles this automatically. Manual chasing is 80% of the time spent on late invoices; automation cuts that to zero.

Add late payment terms (and use them)

UK businesses can charge statutory interest on late payments (currently 8% above the Bank of England base rate) plus debt recovery costs. US: late fees vary by state but are generally enforceable if stated on the invoice. State your late payment terms clearly: 'Late payments accrue interest at 8% above Bank of England base rate, plus a £40 admin fee per the Late Payment of Commercial Debts Act'. You don't have to enforce, but having the terms gives you leverage if needed.

Tips & best practices

▸Always send invoices the day you finish the work, not the end of the month. Clients pay based on receipt date, not work date — invoicing late delays everything.
▸Sequential invoice numbers matter for tax purposes. Don't skip numbers or restart yearly — keep a single sequential count from invoice 001 onwards.
▸Address invoices to the right person. Most A/P departments need a specific contact name; 'Accounts Department' invoices get lost. Ask for the accounts contact when you take on a new client.

Common questions

What information must be on a UK invoice?

Your business name and address, a unique invoice number, the date of issue, your client's name and address, a description of services with quantities and rates, the total amount, and the VAT amount if you're VAT-registered. If you're VAT-registered, you must also include your VAT number.

How long should I give clients to pay?

Net 14 is the modern default for small businesses; Net 7 is reasonable for established clients. Don't use Net 30 by default — it's a leftover from mailed-invoice days and slows your cash flow unnecessarily. For new clients or large amounts, deposit invoices (50% upfront) protect you.

Can I charge late payment fees?

Yes, in most jurisdictions. UK: statutory interest of 8% above BoE base rate plus debt recovery costs is automatic for B2B invoices. US: late fees are generally enforceable if stated on the invoice. Having the terms in writing gives you leverage even if you don't enforce them.

What's the biggest mistake with invoicing?

Inconsistent terms. Mixing 'Pay on receipt', 'Net 14', and 'Net 30' across different invoices creates confusion and gives clients excuses. Pick one term and apply it consistently across all clients.