UK VAT Registration: When and How to Register
Registering for VAT is a milestone for a growing UK business. Register too late and you may owe VAT you never charged; register without thinking it through and you may price yourself out of some customers. This guide explains when registration is compulsory, when it can make sense voluntarily, and how the process works. It is general information, not tax advice, so check GOV.UK or a qualified accountant for your own situation.
Key takeaways
- You must register when your VAT taxable turnover exceeds £90,000 in any rolling 12-month period, or if you expect to go over £90,000 in the next 30 days alone.
- The test is rolling, not based on your tax year, so check your turnover every month.
- Voluntary registration is allowed and can make sense if your customers are mostly VAT-registered businesses.
- Once registered, you charge VAT, keep digital records and file returns through Making Tax Digital software.
For many small businesses, VAT registration arrives quietly. Sales grow month by month, and one day the rolling total crosses the threshold. Owners who are not tracking it can miss the deadline, and HMRC can then ask for the VAT that should have been charged from the date registration was required, often without any way to recover it from customers.
This guide covers the thresholds, how to measure your turnover, the pros and cons of registering voluntarily, the registration steps and what changes once you are registered. If you are new to VAT itself, it helps to understand input and output VAT first, but you can follow this guide without that background.
When you must register for VAT
There are two main tests for compulsory registration in the UK.
- The backward-looking test. At the end of any month, add up your VAT taxable turnover for the previous 12 months. If it is over £90,000, you must register.
- The forward-looking test. If you expect your VAT taxable turnover in the next 30 days alone to exceed £90,000, you must register, even if you have only just started trading.
Each test has its own deadline for telling HMRC and its own effective date of registration. Check the current time limits on GOV.UK as soon as either test is met, because late registration can lead to penalties as well as backdated VAT.
What counts as VAT taxable turnover
VAT taxable turnover is the total value of everything you sell that is not exempt from VAT. It includes standard-rated, reduced-rated and zero-rated sales. It generally excludes exempt sales and sales that are outside the scope of UK VAT. Your total turnover and your VAT taxable turnover may therefore differ, which matters if you make a mix of exempt and taxable sales.
How to track your rolling turnover
The simplest method is a monthly routine. At the end of each month, take the VAT taxable sales for that month from your bookkeeping software or spreadsheet, add them to the previous eleven months, and note the total. A small table with one row per month and a running 12-month total is enough. Many bookkeeping apps can produce a rolling sales report, but check that it excludes exempt and out-of-scope sales.
Set yourself an early warning level well below the threshold. When your rolling total gets close, start checking weekly and look ahead at booked work, large orders or seasonal peaks. The forward-looking 30-day test can catch businesses that land a single large contract, so a big order deserves a quick VAT check before you accept it.
Common mistake
Checking turnover only at your accounting year end. The threshold uses a rolling 12 months, so a strong spring and summer can push you over in the middle of your financial year. Check the rolling total at the end of every month.
Example
For example, a sole trader running a small catering business keeps a simple spreadsheet of monthly sales. At the end of June she adds up July of last year through June of this year and finds a total of £86,000. She books two large wedding contracts for July and August. By the end of August her rolling total is over £90,000, so she registers promptly and starts charging VAT from the correct date, instead of discovering the problem at year end.
Voluntary VAT registration: is it worth it?
You can register for VAT even if your turnover is below £90,000. Whether that is a good idea depends mainly on who your customers are and what you spend.
Reasons to register voluntarily
- You can reclaim VAT on business purchases and equipment
- Your customers are mostly VAT-registered businesses that can reclaim what you charge
- You sell mainly zero-rated goods, so you may receive regular repayments
- You expect to cross the threshold soon and want to set things up calmly
Reasons to wait
- Your customers are consumers who cannot reclaim VAT, so your prices effectively rise
- You have few VAT-bearing costs to reclaim
- You do not want the extra admin of quarterly VAT returns yet
- Your margins are thin and you could not absorb the VAT
Pro tip
Before registering voluntarily, run your last year of sales and costs through a simple model: what would you have charged, what would you have reclaimed, and how would your consumer prices change? Ten minutes with a spreadsheet often makes the decision obvious.
How to register with HMRC
Most businesses register online through their HMRC business tax account. The exact screens change from time to time, but the general process looks like this:
- Gather your details. You will typically need your business name and address, your Unique Taxpayer Reference or company number, bank details, turnover figures and a description of your business activities.
- Sign in to HMRC online services. Use your Government Gateway account, or create one if needed.
- Complete the registration form. Answer questions about your business, your turnover and the date you need to be registered from.
- Consider a VAT scheme. You may be able to apply for schemes such as Flat Rate or Annual Accounting, depending on your turnover and situation.
- Wait for your VAT number. HMRC will confirm your VAT registration number and your effective date of registration.
Some businesses cannot use online registration and must register by post, for example in certain unusual circumstances. GOV.UK explains which route applies. Your accountant can also register on your behalf as your agent.
What changes after you register
Registration changes your day-to-day finances in several ways:
- You charge VAT on taxable sales at the correct rate: standard 20%, reduced 5% or zero 0%.
- You issue VAT invoices showing your VAT number, the rate and the VAT amount.
- You reclaim input VAT on eligible business purchases, supported by valid VAT invoices.
- You keep digital records and file through software. Making Tax Digital for VAT has applied to all VAT-registered businesses since April 2022.
- You file VAT returns and pay on time, usually quarterly.
Updating your prices
Registration forces a pricing decision. If your customers are VAT-registered businesses, you can usually add VAT on top of your existing prices, because they reclaim it. If your customers are consumers, adding 20% on top makes you more expensive, while keeping prices the same means absorbing the VAT and cutting your margin. Many businesses that sell to consumers choose a middle path, reviewing prices product by product. Whatever you decide, update your website, quotes, price lists and checkout before your effective date, and tell regular customers about the change in advance.
Waiting for your VAT number
There is usually a gap between the date you must start accounting for VAT and the day your VAT number arrives. During that gap you cannot show a VAT number on invoices. HMRC guidance explains how to handle this, often by raising your prices to include VAT and issuing proper VAT invoices once the number arrives. Follow the current guidance so customers can reclaim correctly.
Reclaiming VAT on costs before registration
You may be able to reclaim VAT on some goods and services bought before your registration date, within set time limits and conditions. Keep the invoices and check the rules before your first return.
| Situation | What usually applies |
|---|---|
| Rolling 12-month taxable turnover over £90,000 | Compulsory registration |
| Expect over £90,000 in the next 30 days alone | Compulsory registration |
| Turnover below £90,000 | Voluntary registration allowed |
| Turnover falls below £88,000 | You may be able to deregister |
Your VAT registration checklist
- Calculate your rolling 12-month VAT taxable turnover every month
- Watch for any single 30-day period that could exceed £90,000
- Decide whether voluntary registration would help or hurt
- Gather business, bank and turnover details before you apply
- Register online through HMRC or ask your accountant to do it
- Choose MTD-compatible software for VAT records and returns
- Update your prices, invoice template and checkout to include VAT
- Keep invoices for costs that may be reclaimable from before registration
- Add your VAT return deadlines to your calendar
Frequently asked questions
What happens if I register late?
HMRC can require you to pay the VAT you should have charged from the date you were required to be registered, and penalties may apply. Because you did not charge it, this may come out of your own pocket. Register as soon as you realize you have crossed the threshold.
Can I deregister if my turnover drops?
If you expect your VAT taxable turnover to fall below the deregistration threshold of £88,000, you may be able to apply to cancel your registration. Check the conditions on GOV.UK, including any VAT due on stock and assets you keep.
Do I need to register if I only sell zero-rated goods?
Zero-rated sales count toward taxable turnover, so you may cross the threshold. In some cases businesses making mainly zero-rated sales can apply for an exception from registration. Check HMRC's guidance for the details.
Does the threshold apply to each business separately?
VAT registration is generally tied to the legal person, so a sole trader's different trades are usually added together. Splitting a business artificially to stay under the threshold can be challenged by HMRC. Ask an adviser if your structure is complex.
Related reading
The bottom line
UK VAT registration becomes compulsory once your taxable turnover passes £90,000 in a rolling 12 months, or is expected to pass it in the next 30 days alone. Track the rolling total monthly, think about voluntary registration if your customers are businesses, and get your software and invoices ready before your effective date.
Thresholds and procedures change, so treat this as general information and confirm the current rules on GOV.UK or with a qualified accountant before you register.
