The VAT Registration Calculator helps compare a business’s UK taxable turnover with the compulsory VAT registration threshold. It can indicate whether turnover is below, approaching or above the threshold and show the remaining headroom or excess based on the figures entered.

VAT registration is not based on turnover for a fixed accounting year. Most UK-established businesses must monitor taxable turnover over a rolling 12-month period and consider separately whether taxable supplies expected in the next 30 days alone will exceed the threshold.

The calculator provides an illustrative indication rather than an HMRC registration decision. The treatment of exempt, zero-rated, overseas and reverse-charge supplies can require further review before deciding whether and when to register.

How Does the VAT Registration Calculator Work?

The calculator compares the taxable turnover entered with the applicable UK VAT registration threshold and estimates the amount below or above that threshold.

For the 2026/27 tax year, the compulsory VAT registration threshold is £90,000. A UK-established business generally becomes liable to register when either:

its taxable turnover for the previous 12 months goes over £90,000; or
it expects its taxable turnover in the next 30 days alone to go over £90,000.

The threshold is exceeded only when taxable turnover is more than £90,000. Turnover of exactly £90,000 does not exceed it, although further taxable sales may create a registration requirement.

Use the taxable turnover requested by the calculator rather than total business receipts without adjustment. Taxable turnover generally includes standard-rated, reduced-rated and zero-rated supplies but excludes exempt and genuinely outside-the-scope supplies.

HMRC explains the statutory tests and application deadlines in its guidance on when to register for VAT.

What Do the Calculator Results Mean?

The result indicates the business’s position against the threshold, but it does not confirm the final legal registration date or classify individual supplies.

Below the threshold: The taxable turnover entered has not exceeded £90,000. The business should continue monitoring its rolling 12-month turnover and the separate forward-looking test.

Remaining threshold: This is the difference between £90,000 and the taxable turnover entered. It shows the amount of additional taxable turnover that would bring the total to the threshold, not necessarily the amount the business can invoice before registration.

Above the threshold: The entered taxable turnover is more than £90,000. A UK-established business may need to notify HMRC unless an exception or another specific rule applies.

Amount over the threshold: This is the difference between taxable turnover and £90,000. VAT is not charged only on this excess. Once registered, VAT treatment applies to relevant supplies from the effective date of registration.

The calculator cannot determine whether turnover exceeded the threshold in an earlier month. Review each rolling 12-month period, especially where turnover is already close to or above £90,000.

What Is an Illustrative VAT Registration Calculation?

This illustrative example shows how a UK-established business may exceed the rolling 12-month registration threshold.

Illustrative example: At the end of July, a UK-established consultancy calculates that its taxable turnover for the preceding 12 months is £92,500.

The example assumes all £92,500 relates to UK taxable supplies, no VAT has been included in the figure, the business did not exceed the threshold in an earlier month, it is not eligible for an exception from registration and no special overseas, transfer-of-business or artificial-separation rules apply.

Item	Illustrative calculation	Amount
Rolling 12-month taxable turnover	Taxable supplies for the 12 months to 31 July	£92,500
Registration threshold	Current threshold	£90,000
Amount over the threshold	£92,500 − £90,000	£2,500
Notification deadline	30 days after the end of July	30 August
Normal effective registration date	First day of the second month after July	1 September

Based on these assumptions, the calculator would indicate that the threshold has been exceeded by £2,500. The business would normally need to notify HMRC by 30 August, with registration taking effect from 1 September.

The effective date would be different under the forward-looking 30-day test. If the business first expected on 10 July that taxable turnover in the next 30 days alone would exceed £90,000, its effective registration date would normally be 10 July.

What Is Taxable Turnover for VAT Registration?

Taxable turnover is the total value of supplies that are not VAT-exempt or outside the scope of UK VAT, subject to the detailed place-of-supply rules.

Taxable turnover can include:

standard-rated sales;
reduced-rated sales;
zero-rated sales;
goods hired or loaned to customers;
certain business goods used privately;
bartered, part-exchanged or gifted business goods;
certain reverse-charge services received from overseas businesses;
supplies subject to the domestic reverse charge; and
certain building work performed by a business for itself.

Zero-rated supplies still count as taxable turnover even though VAT is charged at 0%. This is different from exempt supplies, which are generally excluded from taxable turnover.

Turnover should be measured using the appropriate VAT tax-point and valuation rules. Cash received into the bank is not always the correct figure, particularly where invoices, deposits, credit notes or non-cash consideration are involved.

Grants, loans, capital introduced by an owner and proceeds from activities outside the scope of VAT are not automatically taxable turnover. Their treatment depends on what the payment relates to.

How Does the Rolling 12-Month Test Work?

The backward-looking test checks taxable turnover for the 12 months ending at the end of every calendar month, rather than only the tax year or accounting year.

At the end of each month, add the taxable turnover from that month and the preceding 11 months. If the total is more than £90,000, the business may have become liable to register.

As a new month is added, the oldest month drops out of the calculation. The total can therefore rise or fall even where the business’s annual accounts have not been completed.

Review date	Period to include
31 July 2026	1 August 2025 to 31 July 2026
31 August 2026	1 September 2025 to 31 August 2026
30 September 2026	1 October 2025 to 30 September 2026

A business should not wait until its financial year end to perform this test. Monthly records can help identify the first period in which the threshold was exceeded and establish the correct notification deadline.

How Does the 30-Day Forward-Looking Test Work?

A business must consider whether taxable turnover expected in the next 30 days alone will exceed £90,000, even if its previous 12-month turnover is below the threshold.

This test can apply when a business accepts a large contract or reasonably expects a concentration of taxable sales within a single 30-day period.

The test does not ask whether cumulative turnover will exceed £90,000 at some point during the next year. It asks whether supplies expected in the next 30 days alone will be more than £90,000.

The effective date of registration is normally the date on which the expectation first arose. The business must generally notify HMRC by the end of the following 30-day period.

For example, if a business agrees a taxable £100,000 contract on 1 May and expects to make the supply within the next 30 days, it may need to register by 30 May with an effective registration date of 1 May, subject to the detailed circumstances.

When Must a Business Apply for VAT Registration?

The application deadline and effective date depend on whether liability arises under the backward-looking or forward-looking test.

Registration test	Application deadline	Normal effective date
Previous 12-month turnover exceeds £90,000	Within 30 days of the end of the month in which the threshold was exceeded	First day of the second month after the threshold was exceeded
Expected turnover in the next 30 days alone exceeds £90,000	By the end of that 30-day period	Date the expectation first arose

Registration can be backdated where a business applies late. The business may then owe VAT on relevant supplies made from the correct effective date even if it did not charge customers VAT at the time.

A failure-to-notify penalty and interest may also arise, depending on the circumstances and the amount of VAT unpaid. Businesses that may already be late should establish the earliest date of liability and contact HMRC or a qualified adviser promptly.

Can a Business Register Voluntarily?

A business making or intending to make taxable supplies can generally apply for voluntary VAT registration before its turnover exceeds £90,000.

Voluntary registration may allow a business to recover eligible input VAT on costs. It may be useful where customers are VAT-registered businesses that can normally recover the VAT charged to them.

However, registration also creates obligations. A registered business will usually need to:

charge the correct VAT rate on taxable supplies;
issue valid VAT invoices where required;
keep appropriate digital VAT records;
submit VAT returns through compatible software;
pay net VAT to HMRC by the applicable deadline; and
apply the correct rules to input tax claims.

Voluntary registration can affect prices or margins where customers cannot recover VAT. Consider the customer base, recoverable input tax, administrative cost and pricing strategy before applying.

Can a Business Avoid Registration After Temporarily Exceeding the Threshold?

A business may apply for an exception from registration if the threshold was exceeded temporarily and future taxable turnover is expected to stay below the deregistration threshold.

The VAT deregistration threshold is £88,000 for 2026/27. A business that exceeds the £90,000 registration threshold under the backward-looking test may ask HMRC for an exception if it can demonstrate that taxable turnover in the following 12 months is not expected to exceed £88,000.

The exception is not automatic. The business must apply to HMRC and provide evidence supporting its forecast, such as the loss of a one-off contract or another identifiable reduction in taxable activity.

The business should still notify HMRC within the applicable registration period. It should not simply decide that registration is unnecessary because a single unusual sale caused the threshold breach.

Do Exempt and Zero-Rated Sales Count Towards the Threshold?

Zero-rated sales generally count towards taxable turnover, while exempt sales generally do not.

Zero-rated supplies are taxable supplies charged at 0%. Examples can include qualifying food, children’s clothing, books and certain exports, subject to detailed conditions.

Exempt supplies are not taxable supplies for registration-threshold purposes. Potential examples include certain insurance, finance, education, healthcare and property transactions, depending on the precise facts and statutory rules.

A business making both taxable and exempt supplies should include the taxable supplies and exclude only those supplies that are correctly classified as exempt or outside the scope.

Incorrectly treating zero-rated sales as exempt can significantly understate taxable turnover and delay registration.

Do Overseas Businesses Use the £90,000 Threshold?

A business with no UK establishment may be required to register from its first UK taxable supply, without the benefit of the normal £90,000 threshold.

The rules for a non-established taxable person depend on whether it makes, or expects to make, taxable supplies in the UK. Place-of-supply, reverse-charge and online marketplace rules can affect whether a UK taxable supply exists.

An overseas business should not rely solely on a threshold comparison. It may have a registration obligation even where the amount shown by the calculator is substantially below £90,000.

Separate rules may also apply to goods sold into or from Northern Ireland, distance sales, acquisitions, imports and digital services.

Can Connected Businesses Use Separate VAT Thresholds?

Separate legal businesses may each have their own threshold, but HMRC can act where business activities have been artificially separated to avoid VAT registration.

Factors that may indicate artificial separation include:

common financial control;
shared premises, equipment or staff;
closely linked customers or suppliers;
businesses offering complementary parts of the same service;
common branding, websites or contact details; and
one commercial operation being divided without a genuine business reason.

The existence of family ownership or shared premises does not by itself determine the answer. HMRC considers the financial, economic and organisational links between the activities.

The calculator reviews the turnover entered. It cannot determine whether HMRC would aggregate artificially separated activities or treat several entities as one business for registration purposes.

What Factors Can Affect the Calculator Result?

The turnover period, VAT classification, place of supply and business establishment can materially change the registration position.

Rolling period: The relevant backward-looking period changes at the end of every month.
Standard-rated sales: These normally count in full towards taxable turnover.
Reduced-rated sales: These also normally count in full, not merely at the reduced VAT percentage.
Zero-rated sales: These generally count despite no VAT being charged.
Exempt supplies: Correctly exempt turnover is generally excluded.
Outside-the-scope income: This may be excluded, subject to the underlying transaction and place-of-supply rules.
Credit notes and cancellations: These can affect the value and timing of supplies.
Large contracts: A contract may trigger the separate next-30-days test.
Overseas establishment: A non-established business may not have a registration threshold.
Connected activities: Artificial separation rules may require linked operations to be considered together.
Historical thresholds: A different threshold may apply when reviewing an earlier registration date.

Where classification is uncertain, review the supply itself rather than relying on how it appears in the business accounts.

What Common VAT Registration Mistakes Should Be Avoided?

Common mistakes include using annual accounts instead of a rolling period, excluding zero-rated sales and applying the £90,000 threshold to every business.

Checking only the financial year

The normal backward-looking test must be performed using rolling 12-month turnover at the end of each calendar month.

Annual accounts can support the calculation but may not reveal the first month in which the threshold was exceeded.

Including all receipts without reviewing them

Business receipts are not automatically the same as taxable turnover.

Review loans, grants, capital contributions, asset sales, deposits and overseas income according to the relevant VAT rules.

Excluding zero-rated supplies

Zero-rated supplies normally count towards the registration threshold even though their VAT rate is 0%.

Do not treat zero-rated and exempt supplies as interchangeable.

Including exempt turnover

Correctly exempt supplies are generally excluded from taxable turnover.

Classification can be fact-specific, so confirm that the statutory exemption actually applies.

Looking only at expected annual turnover

The forward-looking test concerns turnover expected in the next 30 days alone, not an ordinary 12-month forecast.

A large one-off contract can therefore trigger registration immediately even where normal annual turnover is much lower.

Charging VAT before receiving a VAT number

A business should not issue an invoice showing VAT as VAT until HMRC has provided its registration number.

While waiting, the business may adjust its price to allow for VAT and later issue a valid VAT invoice after receiving the number, following HMRC guidance.

Assuming only the excess is subject to VAT

VAT is not calculated solely on turnover above £90,000.

From the effective registration date, the business must account for VAT on relevant taxable supplies according to their proper rates.

What Are the Calculator’s Important Limitations?

The calculator compares entered turnover with the threshold but cannot determine every supply’s VAT status or establish a definitive registration date.

The result may require adjustment where the business has:

exempt or partly exempt activities;
zero-rated supplies;
sales or purchases involving other countries;
reverse-charge transactions;
supplies made through an online marketplace;
transactions involving Northern Ireland;
connected or potentially separated business activities;
a transfer of a business as a going concern;
a large one-off contract;
historic threshold breaches; or
no established business presence in the UK.

The calculator does not register the business, notify HMRC, calculate penalties or determine whether an exception from registration will be accepted.

Taxable turnover should be supported by appropriate sales records and reviewed monthly. If the threshold may have been exceeded previously, use the threshold and rules that applied at the relevant time rather than automatically applying the current figure.

Which Related Calculators May Be Useful?

Related VAT calculators can help estimate invoice VAT and consider accounting options after the registration position has been reviewed.

The VAT Calculator can add or remove VAT from an amount using standard, reduced and zero rates. It does not determine whether a supply qualifies for a particular rate.

The Reverse VAT Calculator can extract the VAT element from a VAT-inclusive price after the correct rate has been established.

Eligible small businesses can use the VAT Flat Rate Calculator to estimate VAT under the Flat Rate Scheme. The scheme has separate eligibility and turnover rules and does not replace the registration test.

This VAT Registration Calculator provides estimates only. Results depend on the turnover, period and assumptions entered, while the VAT treatment of supplies, reliefs and business circumstances can differ. The calculator does not confirm registration liability or replace HMRC guidance, and professional VAT advice may be appropriate for uncertain, overseas, exempt, connected or historic transactions.

VAT Registration Calculator UK

How this calculator works