Why these guides exist
Invoicing looks simple until you ask a precise question: does this need a VAT number, is a deposit taxable, how long must I keep this, what do I write when the customer is in another country. Official answers exist, but they are spread across tax authority sites and written for specialists. Our guides translate them into plain language, link to the primary source for every rule, and tell you when a point needs checking with your own authority.
Each guide is written to be used. There are checklists you can follow, tables you can scan, worked examples with clearly illustrative numbers, and the matching tool one click away. We do not publish invented statistics, and we do not pretend that one article can replace an accountant. See our editorial policy for how we research, review and correct.
How to use the guides
- Start with what to include on an invoice if you are new.
- Choose your country’s guide for the tax details: UK VAT, US sales tax, Canada GST/HST, Australia GST or New Zealand.
- Use the cash-flow guides to get paid faster and to handle late payers.
- Open the linked generator or calculator and make the document.
Sources and accuracy
Every guide lists official sources such as GOV.UK, the IRS, the Canada Revenue Agency, the Australian Taxation Office, Inland Revenue New Zealand and the European Commission. Tax rules, thresholds and deadlines change, sometimes within weeks. Each guide shows the month we last reviewed it. Where we could not fully confirm a detail we say so and ask you to check official guidance. None of this is legal, tax or accounting advice. Read the disclaimer.
Frequently asked questions
Are the guides free?
Yes. There is no sign-up and no paywall.
Who writes the guides?
The InvoiceDesk editorial team. Our editorial policy explains how we research and correct them.
Can I rely on them for tax filings?
No. They are general information. Check the official source and ask a qualified adviser about your situation.
How often are they updated?
We review them when rules change and at least every few months. Each page shows the date it was last reviewed.
I found a mistake. What do I do?
Please email us from the contact page. We correct errors and note significant changes.
Do you cover countries other than the US, UK, Canada, Australia and New Zealand?
We cover the EU in the reverse-charge and e-invoicing guides and have generator pages for several European countries. More country guides will follow.
Where are the tools?
See the tools page for all invoice generators and calculators.
Can I link to a guide?
Yes. Please link to the page rather than copying the text.
Related topics
- invoicing guides
- invoice rules by country
- VAT invoice guide
- GST invoice guide
- freelance invoicing tips
- late payment help
- e-invoicing guide