UK VAT Registration Guide: Thresholds, Timing, and Voluntary Registration

For UK businesses, VAT registration is the most consequential tax decision in the early growth phase. The £90,000 threshold is fixed; it has been frozen at this level since April 2024. The compulsory trigger applies on any rolling 12-month period — not the calendar or accounting year. The forward-looking trigger applies if turnover is expected to exceed £90,000 in the next 30 days alone. Voluntary registration below the threshold can pay back where input VAT recovery exceeds output VAT. VAT grouping consolidates multiple companies under a single registration. Disaggregation (artificially splitting a business to stay below the threshold) is an HMRC enforcement priority. TOGC (Transfer of a Going Concern) provides a strict VAT exemption on business sales. Pre-registration VAT reclaim recovers input VAT on goods and services bought before registration. And deregistration at £88,000 carries asset-tax-charge consequences.

The £90,000 threshold: rolling 12-month vs forward look

Two separate triggers:

1. 1Backward-looking (rolling 12-month): turnover in any rolling 12-month period exceeded £90,000. Must register within 30 days of crossing.
2. 2Forward-looking (next 30 days): expected turnover in the next 30 days alone exceeds £90,000. Must register from the date the expectation arose.
3. 3Either trigger compels registration; meeting either is sufficient.
4. 4Calculation: include all UK taxable supplies (standard, reduced, zero-rated). Exclude exempt supplies, capital asset disposals, and outside-the-scope supplies.

Voluntary VAT registration

Below the threshold, a business can voluntarily register. The economic case:

• B2B businesses where most customers can recover input VAT (the 20% surcharge is invisible to them).
• High input VAT environments (lots of expense VAT to recover).
• Capital-intensive startups where pre-registration purchases include significant VAT.
• Businesses approaching the threshold within 6-12 months: voluntary registration smooths the customer-facing transition.

Voluntary registration is rarely worthwhile for B2C consumer-facing businesses below the threshold: the 20% VAT surcharge is felt directly by the customer and erodes pricing competitiveness against unregistered competitors.

VAT grouping post-2024

VAT grouping treats multiple companies under common control as a single VAT entity:

• Eligibility: corporate bodies under common control (50%+ voting rights or board control).
• Group submits a single VAT return covering all members.
• Intra-group supplies are disregarded for VAT purposes.
• Joint and several liability: each group member is liable for the group's VAT debt.
• Cross-border grouping post-Brexit: limited to UK-resident companies.
• The 2026 HMRC rule changes tightened anti-avoidance provisions for VAT grouping where one member would otherwise be partially exempt.

Artificial separation: HMRC's view

HMRC's disaggregation factors:

• Common premises, staff, equipment.
• Common customer base or shared marketing.
• Financial interdependence (one funding the other).
• Common control or family relationships between operators.
• Lack of arm's-length pricing between the entities.

Transfer of a Going Concern (TOGC)

TOGC provides a strict VAT exemption on the sale of a business as a going concern:

1. 1Both seller and buyer must be VAT-registered (or buyer obligated to register on transfer).
2. 2The buyer must continue the same kind of business as the seller.
3. 3There must be no significant break in trading.
4. 4For property included in the sale: any option to tax must transfer with the property.
5. 5TOGC treatment is automatic when conditions are met; HMRC clearance not required but recommended for high-value transactions.

Pre-registration VAT reclaim

On registration, businesses can reclaim input VAT on:

1. 1Goods purchased in the 4 years before registration that remain on hand at registration date.
2. 2Services purchased in the 6 months before registration directly relevant to the business.
3. 3Capital assets used by the business at registration date.
4. 4Documentation: must hold valid VAT invoices for all reclaim items.
5. 5Adjusted on the first VAT return after registration.

Deregistration: the £88,000 exit threshold

A business can deregister voluntarily when turnover falls below £88,000:

• Application via VAT7 form to HMRC.
• Deregistration takes effect from the date HMRC approves.
• Final return covers the period to deregistration date.
• Output VAT charge: on stocks, fixed assets and capital items remaining at deregistration where input VAT was previously reclaimed AND the value exceeds £6,000.
• Property held under option to tax: deregistration does not automatically revoke OTT.