Do I need to register for VAT as a sole trader? The £90,000 threshold explained

A sole trader must register for VAT when VAT-taxable turnover goes over the registration threshold. The key point many people miss is that the £90,000 threshold is measured on a rolling 12-month basis, not just at the end of the tax year.

The £90,000 VAT threshold

You must register if your VAT-taxable turnover for the last 12 months is more than £90,000, or if you expect it to go over £90,000 in the next 30 days alone. VAT-taxable turnover means sales that are not exempt from VAT. It is turnover before expenses, not profit.

Check your headroom with the VAT threshold checker. If you are close to the limit, review turnover every month rather than waiting for Self Assessment.

Mandatory vs voluntary registration

Mandatory registration means HMRC requires you to register because you have crossed the threshold. Voluntary registration means you register even though you are below the threshold. Some sole traders register voluntarily because they sell to VAT-registered businesses, want to reclaim VAT on costs, or want to appear more established.

Voluntary registration can hurt if most customers are consumers or small non-VAT-registered businesses, because adding VAT may make your prices look 20% higher unless you absorb some of the cost.

When VAT helps cash flow

VAT can help cash flow when your customers are VAT registered and can reclaim the VAT you charge. In that case, adding VAT may not make you more expensive to them, while you may be able to reclaim VAT on eligible business purchases. It can hurt cash flow if you collect VAT but forget that it belongs to HMRC.

The Flat Rate Scheme

The Flat Rate Scheme can simplify VAT accounting for some small businesses. Instead of reclaiming VAT on most purchases, you pay HMRC a fixed percentage of your VAT-inclusive turnover based on your business type. It can be administratively simpler, but it is not automatically cheaper, especially for limited-cost traders.

Pricing and invoices after registration

Once registered, you need to charge VAT where it applies, issue VAT invoices, keep VAT records, submit VAT returns, and usually use Making Tax Digital compatible software for VAT. Use the VAT add/remove calculator to check net, VAT, and gross amounts before quoting or invoicing.

Common mistakes

Checking the threshold only once a year instead of using a rolling 12-month total.
Looking at profit instead of VAT-taxable turnover.
Registering voluntarily without checking customer price sensitivity.
Spending VAT collected from customers instead of setting it aside.
Assuming all sales are treated the same for VAT.

Official sources

GOV.UK explains registration here: Register for VAT. The Flat Rate Scheme guidance is here: VAT Flat Rate Scheme.