VAT Return Calculator UK

Enter your output VAT and input VAT to calculate your net VAT payable or reclaimable. Includes a box-by-box guide to completing your VAT100 return and an MTD quarterly deadline calculator.

VAT & InvoicingUpdated for 2026/27
VAT return figures
£
The total VAT you have charged to your customers during the period.
£
The total VAT you have paid on business purchases and expenses during the period.
£
£
Enter your quarter end date to calculate the filing and payment deadline.

Frequently asked questions

Box 1 is the VAT due on your sales and other outputs (output tax). This is the VAT you have charged on your VAT invoices during the period. It also includes any VAT due on goods you have taken from stock for personal use, reverse charge VAT on services received from abroad, and VAT on goods acquired from EU countries (now primarily via import procedures post-Brexit).

Under the cash accounting scheme you account for VAT on the basis of payments received and made rather than invoices issued and received. This means you do not pay output VAT until your customer pays you, which helps cash flow for businesses with slow-paying customers. The scheme is available to businesses with taxable turnover up to £1.35 million.

Most VAT-registered businesses submit quarterly returns. However, you can apply to submit annual returns if your turnover is below £1.35 million. HMRC can also direct high-risk businesses to submit monthly returns. Under Making Tax Digital, returns must be submitted digitally using compatible software within one month and 7 days of the end of each VAT period.

If your input VAT exceeds your output VAT for the period, you can claim a refund. HMRC aims to process most repayments within 30 days. During busier periods or for new businesses, HMRC may conduct a verification check before repaying, which can delay the refund. Repayment traders (those regularly in a refund position) may be put on monthly returns.

Under the annual accounting scheme you submit one VAT return per year instead of quarterly. You make interim payments (either 9 monthly or 3 quarterly instalments) based on your previous year's VAT liability, then make a balancing payment or claim a refund when you submit the annual return. The scheme reduces administrative burden but means you cannot reclaim VAT refunds during the year.