VAT vs Sales Tax vs GST: What’s Actually the Difference
Plain-English guide 4 calculators linked No sign-up
Three tax systems, three different sets of rules. Here’s what actually changes between VAT, sales tax, and GST.
Last year, I had three invoices due in the same week. One client was in London. One was in Sydney. One was in Toronto. I sat down to bill all three, and for a moment I genuinely mixed up the rules. I almost charged the Australian client the UK VAT rate. That mistake would have cost me an awkward correction email, or worse, an underpaid invoice.
That mix-up is exactly why this guide exists. VAT, sales tax, and GST all do a similar job. They all add tax to a sale. But the mechanics behind each one are genuinely different, and mixing them up is an easy mistake to make, especially when you’re juggling clients across borders.
So here’s the plain-English version. No jargon, just the actual differences, plus a real example so you can see each system in action. If you only remember one thing from this guide, remember this: VAT vs sales tax vs GST isn’t really a fight over which tax is “worse.” It’s a difference in mechanics, and that difference changes how you invoice.
What VAT actually is
VAT stands for Value Added Tax. The UK and the European Union both use it. Here’s the key idea: the tax applies at every stage of a supply chain, not just at the final sale.
A manufacturer charges VAT to a wholesaler. The wholesaler charges VAT to a retailer. The retailer charges VAT to the final customer. Each business in the chain can reclaim the VAT it paid on its own purchases. Only the “value added” at each step actually gets taxed. As a freelancer, you mostly handle the final step. You charge VAT on your own invoices, if you’re VAT-registered.
Our UK VAT Calculator handles this exact calculation, using the standard 20% rate. For a more formal definition, Investopedia’s explainer on value-added tax covers the underlying economic theory in more depth than we will here.
What sales tax actually is
Sales tax, used in the US, works differently. It skips the multi-stage system entirely. Sellers charge it just once, at the final point of sale to the end customer. A manufacturer doesn’t charge sales tax to a wholesaler. Only the last sale, to the actual buyer, includes the tax.
Sales tax also isn’t set nationally. Each US state sets its own rate, and many cities and counties add their own local tax on top. That’s why “US sales tax” isn’t one single number the way UK VAT is. Our USA Sales Tax Calculator covers the base rate for all 50 states.
What GST actually is
GST stands for Goods and Services Tax. Australia and Canada both use this name, but they apply it differently.
In Australia, GST is simple. Sellers charge a flat 10% on most goods and services, and it moves through the supply chain the same way VAT does. Our Australia GST Calculator uses this flat rate directly.
In Canada, it’s more complex. The federal GST rate is 5%, but individual provinces add their own layer on top. Some provinces combine the two into a single number called HST. This is why an invoice in Ontario looks completely different from one in Alberta. Our Canada GST/HST Calculator handles this by province.
The core difference: where the tax gets collected
Here’s the part that actually matters for your invoicing. VAT and Australian GST both work incrementally — each business along the supply chain adds its share. US sales tax works differently. It only applies once, at the final sale. Canadian GST/HST sits somewhere in between, depending on the province.
This difference explains something important. VAT-registered businesses can reclaim the VAT they paid on their own purchases. A US retailer generally can’t do the same with sales tax. The end result to the final customer looks similar. The mechanics behind it are not.
A side-by-side example
Say you’re invoicing $1,000 worth of work to four different clients, one in each country. Here’s how the tax portion compares:
| Country | System | Rate | Tax on $1,000 |
|---|---|---|---|
| UK | VAT | 20% | $200 |
| Australia | GST | 10% | $100 |
| Canada (Ontario) | HST | 13% | $130 |
| USA (California) | Sales tax | 7.25% | $72.50 |
The takeaway: the exact same $1,000 invoice results in four completely different tax amounts, purely based on which country your client is in. This is exactly why a single “add 20%” habit doesn’t work once you start billing internationally.
Which calculator applies to you
If your client is in the UK, use VAT. If they’re in Australia, use GST at the flat 10% rate. If they’re in Canada, check the specific province, since the rate genuinely changes depending on where they’re based. If they’re in the US, check the specific state, since sales tax varies there too.
Not sure which one fits your exact situation? Our full guides page covers more specific scenarios, including whether freelancers need to charge VAT at all.
The short version of VAT vs sales tax vs GST
To sum up VAT vs sales tax vs GST in one line each: the UK applies VAT at every stage. The US applies sales tax once, at the final sale. Australia and Canada both use GST, but Australia runs it like VAT, while Canada runs a hybrid system that varies by province. Once you know which one applies to your client, the actual math is simple — that’s exactly what our calculators handle for you.