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Guides

Straight answers to specific questions.

Reference guides for the questions that come up over and over when you're invoicing clients: VAT, numbering, retention, and the difference between an invoice and a receipt.

How to calculate VAT on an invoice

A worked example of calculating VAT on an invoice, including how to handle multiple VAT rates on the same invoice.

4 min read

Invoice vs receipt: what's the difference

The practical difference between an invoice and a receipt, when you need each one, and why confusing them causes accounting problems.

3 min read

What is a pro forma invoice and when do you need one

What a pro forma invoice is, how it differs from a standard invoice, and the situations where clients specifically ask for one.

3 min read

How long do you need to keep invoices for tax purposes

General retention guidance for invoices and financial records in the UK and US, and practical tips for actually keeping them organised.

3 min read

What is an invoice number and how should you format it

What an invoice number is for, why it needs to be unique and sequential, and practical formatting options for different business sizes.

3 min read

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