What is VAT and do I actually have to charge it?

The tax that makes founders panic at £90k

There's a moment a lot of growing UK businesses hit. Sales are going well, the bank balance looks healthy, and then someone says the word: VAT. Suddenly there's a threshold, a registration, a quarterly return, and a quiet fear that you've been doing something wrong.

Take a breath. VAT is one of the most misunderstood things in small business, and almost all of the fear comes from not knowing what it actually is. So let's fix that. By the end of this page you'll know what VAT is, when you have to charge it, what the rates mean, and why — done right — it isn't your money flowing out, just money passing through you.

This page stays on the "what" and the "when." How to actually file a return is its own thing, and we'll point you there at the end.

What VAT actually is

VAT stands for Value Added Tax. It's a tax on most goods and services sold in the UK. The key thing to understand — the thing that makes everything else click — is who really pays it.

The customer pays VAT. You just collect it.

When you're VAT-registered, you add VAT on top of your prices. Your customer hands it over along with the bill. Then, every quarter, you pass that collected VAT to HMRC. You're not paying it out of your own pocket — you're a collection point between your customer and the taxman. The VAT was never really yours; it was always on its way to HMRC.

That single idea defuses most of the panic. The number on your VAT return looks scary, but it's largely money you already collected from customers specifically to hand over. Your job is to not spend it in the meantime.

Do you even have to charge it? The £90,000 threshold

Here's the part everyone actually wants to know. You don't have to charge VAT just because you have a business. You have to register for VAT — and start charging it — once your taxable turnover passes £90,000 in any rolling 12-month period.

A few plain-English points hidden in that sentence:

"Turnover," not profit. It's your total sales, before costs. You could be making very little profit and still cross the threshold.

"Rolling 12 months," not your tax year. This trips people up. It's not "did I do £90k last year?" It's "in any 12 months ending this month, did my sales pass £90k?" You check it on a rolling basis, which is why it can sneak up on a growing business mid-year.

You must register quickly once you cross it. There's a deadline (and a separate test if you expect to cross it within the next 30 days), so it's worth watching your trailing 12-month total as you grow, not just glancing once a year.

Below £90,000, you generally don't have to charge VAT at all. You can choose to register voluntarily — some businesses do, usually to reclaim VAT on their own purchases or to look established to bigger clients — but you're not forced to.

So the honest answer to "do I have to charge it?" is: only once your rolling 12-month sales pass £90,000, or if you choose to register early.

The rates: standard, reduced and zero

Not everything is taxed at the same rate. There are three main VAT rates in the UK, plus a couple of categories that sit outside the system entirely.

Standard rate — 20%. This is the default, and what most goods and services use. Unless you know otherwise, assume your sales are standard-rated.

Reduced rate — 5%. A smaller rate for specific things — for example, domestic energy and certain home improvements. It's a defined list, not a judgement call.

Zero rate — 0%. Some things are taxable but charged at 0% — most food, children's clothing, books, and more. "Zero-rated" still counts as a taxable sale (so it counts towards your threshold and goes on your return), it's just charged at nothing.

Two more categories worth knowing, because they're not the same as zero-rated:

Exempt. Some things — like certain financial services, insurance and some education — are exempt from VAT entirely. You don't charge VAT and these sales don't count as taxable turnover.

Outside the scope. Some things sit completely outside VAT's reach.

The difference between zero-rated and exempt sounds like hair-splitting, but it affects whether you can reclaim VAT on related costs — which is exactly the kind of thing an accountant or your software should flag, not something you should lose sleep memorising.

Input vs output VAT: the bit that sounds clever but isn't

Here's the mechanism that confuses people, explained as simply as it gets.

Output VAT is the VAT you charge your customers. (Think: VAT going out to HMRC on your sales.)

Input VAT is the VAT you pay on your own purchases — your software, stock, equipment, the things you buy to run the business. (Think: VAT coming in on your costs.)

When you do your VAT return, you don't just hand over everything you collected. You subtract the VAT you paid from the VAT you charged, and send HMRC the difference.

A quick example. In a quarter you charge customers £10,000 of VAT (your output VAT). Over the same quarter you paid £3,000 of VAT on your own purchases (your input VAT). You owe HMRC £10,000 − £3,000 = £7,000. You keep the rest because you already paid it out on your costs.

And if you paid more VAT on purchases than you charged on sales — common when you've made a big investment — HMRC actually pays you the difference back. The system is designed so VAT lands on the final customer, not on you, by letting you claw back what you paid along the way.

That's the whole engine: VAT out, minus VAT in, equals what changes hands with HMRC.

Where VAT shows up in your numbers

VAT isn't profit and it isn't a cost — it's money in transit, which is why it deserves its own mental box.

On your invoices, the VAT is shown as a separate line on top of your price. On your balance sheet, VAT you've collected but not yet paid sits as a liability (money owed by you to HMRC) until you hand it over — which is precisely why you shouldn't think of a VAT-flush bank balance as "yours." Some of it belongs to HMRC and is just waiting for the next return. Forgetting that is one of the classic ways founders feel rich one month and squeezed the next. (See: What is a balance sheet? → and Profit vs cash — why you can be profitable and still broke →.)

Why this is worth understanding even if someone else files it

You might never touch the return yourself. You should still understand VAT, for two reasons.

First, it affects your pricing. Crossing the threshold means adding 20% to your prices (or absorbing it). For a business selling to consumers, that's a real decision, and you want to see it coming, not get surprised by it mid-quarter.

Second and most importantly, the VAT you collect isn't yours to spend. Treat it as money you're holding for HMRC, set it aside as it comes in, and the quarterly return becomes a non-event instead of a scramble. The founders who get caught out are the ones who spent the VAT and then had to find it again three months later.

The short version

VAT is a tax on most UK sales that your customers pay and you collect on HMRC's behalf. You must register once your rolling 12-month turnover passes £90,000 (you can register voluntarily below that). Most things are taxed at the standard 20%, some at a reduced 5% or zero rate, and a few are exempt or outside the scope entirely. When you file, you subtract the VAT you paid on purchases (input VAT) from the VAT you charged customers (output VAT) and pay HMRC the difference. It's money passing through you — so don't spend it.

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VAT is mostly stressful when it's a manual job. In Ledgers, VAT is tracked automatically as you invoice and spend, your return is generated for you with anomaly checks before you sign off, and it's fully Making Tax Digital compatible — so the quarterly return stops being a scramble. See your numbers without learning accounting → start free.

Ready to stop doing this by hand? Here's the practical walk-through: How to file a VAT return (without an accountant) →

Want to understand where VAT sits in your wider numbers? What is a balance sheet? →

Frequently asked questions

What does VAT stand for?

Value Added Tax. It's a tax on most goods and services sold in the UK. Customers pay it and VAT-registered businesses collect it and pass it to HMRC.

What is the VAT registration threshold in the UK?

£90,000 of taxable turnover in any rolling 12-month period. Once you cross it you must register and start charging VAT. Below it, registration is optional.

Do I have to charge VAT if I'm under the threshold?

No. Under £90,000 you generally don't have to charge VAT at all. You can choose to register voluntarily — often to reclaim VAT on your purchases — but you're not required to.

What's the difference between input and output VAT?

Output VAT is the VAT you charge customers on your sales. Input VAT is the VAT you pay on your own purchases. On your return you subtract input from output and pay HMRC the difference.

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