Checking a tax calculation document

Accepted documents

A digital PDF of an HMRC tax calculation (SA302), up to 5 MB, or a CSV of the same figures, up to 1 MB. The file type is checked from its contents, not its name.

Scanned or photographed PDFs have no text to read, so FLYNQD says so rather than guessing; text recognition isn't available. Other file types, damaged files and documents FLYNQD doesn't recognise as a tax calculation are turned away with the reason. Statements such as a P60 or a bank statement aren't checked.

2023/24, 2024/25 and 2025/26 are supported, for the rest of the UK. Scottish taxpayers and other years are shown as unsupported. All three years have matched HMRC's own calculation figures line for line, including, for 2023/24, a case with a Gift Aid tax charge and VCT relief larger than the tax due. For 2023/24 the check covers Income Tax and Capital Gains Tax; employee National Insurance isn’t compared, because the rate changed on 6 January 2024 and depends on when you were paid.

How figures are extracted

FLYNQD reads the text in your browser, finds the tax year, and picks out each figure it recognises, such as pay from employment, interest, dividends, reliefs and the Income Tax due. Each figure keeps the page and line it came from so you can check it against the document.

If a document covers more than one tax year, none is chosen until you pick one. If the same item appears twice with the same amount it's used once; if the amounts differ you choose which is right.

Confirming and correcting figures

The check has three stages: A, review your income and reliefs; B, FLYNQD checks the calculation; C, compare results with HMRC.

In stage A you confirm the document type, the tax year and that it's for the person you're viewing, then confirm, correct or exclude each financial input, such as pay from employment, benefits, interest, dividends and Gift Aid you paid. Only these feed FLYNQD's calculation.

HMRC's own calculated figures, such as total income, the Personal Allowance, taxable income, the Gift Aid band extension and revised basic-rate limit, Income Tax before and after reductions and the final Income Tax due, are shown in stage B as the HMRC calculation. They're read as printed and never need confirming; FLYNQD works each one out independently and compares. Where a reduction such as VCT relief is larger than the tax it can reduce, the relief actually used is shown alongside the amount claimed.

Matches is shown only when every input and relief question has been answered and FLYNQD's own calculation is complete, with HMRC's Income Tax, FLYNQD's Income Tax and the difference side by side.

To correct a figure, choose Correct, enter the right amount and save. The figure is marked “Corrected by you” and the document's own amount is kept next to it. Excluding a figure leaves it out entirely.

Some reliefs need an answer before they can be used: what a loss relief is for, whether a VCT was approved, and whether Gift Aid is the amount you paid. FLYNQD never assumes the answer. If a figure the calculation needs isn't in the document, such as a VCT subscription, you can add it.

Gift Aid on a tax calculation

A tax calculation can show four different Gift Aid figures, and FLYNQD keeps them apart:

The donation is what you actually paid the charity. The grossed-up donation is that amount plus the basic-rate tax the charity reclaims, so a £100 payment is £125 grossed up. The band extension is the grossed-up amount by which your basic-rate limit is raised. The new limit is what the band becomes: “increased by £269 to £37,969” means the extension is £269 and the limit is £37,969. Neither figure is a donation.

The Gift Aid tax charge applies when you haven't paid enough tax to cover what the charity reclaims. HMRC adds it back as basic-rate tax on the uncovered amount, as in “£269 at 20% = £53.00”. It's a tax charge, not a payment to charity.

A calculation usually shows only the band extension, not what you paid. FLYNQD can work the donation out from it (extension × 80%) only if you confirm that's right, and records that as an assumption. The extension is rounded to whole pounds, so the donation worked out from it may be a few pence off what you paid; it doesn't change the tax.

VCT relief

Venture Capital Trust relief is a reduction in Income Tax of up to 30% of the amount subscribed for newly issued shares in an approved VCT. Shares bought second-hand don't qualify.

The relief can only reduce Income Tax to nil. It can't create a refund or be carried to another year, and it doesn't reduce a Gift Aid tax charge or Capital Gains Tax. FLYNQD shows the relief claimed and the part actually used separately, so a £6,000 claim against £4,020.62 of tax shows £4,020.62 used.

If the calculation shows only the relief, FLYNQD can work out the subscription (relief ÷ 30%) once you confirm that, and records it as an assumption.

How FLYNQD calculates independently

FLYNQD uses the income and relief figures you've confirmed and that year's rates and allowances to work out its own Income Tax, using the same calculation as the rest of the Tax page. The document's results, such as taxable income and Income Tax due, are only ever compared with; they're never used as inputs.

Capital Gains Tax on the document is shown for reference only and isn't compared.

What the result means

Matches: FLYNQD's figures agree with the document, line for line, to the penny.

Difference: at least one line differs, and the amount is shown. A difference is a prompt to check the figures and your answers, not proof that either calculation is wrong.

Missing information or Needs your confirmation: something needed hasn't been found or confirmed, so FLYNQD gives no result rather than a partial or guessed one, and lists what's needed.

Unsupported: the document includes a year, a part of the UK or a tax treatment FLYNQD doesn't calculate, for example a loss relief that isn't for shares in a qualifying trading company, or a negative income figure. It's named rather than forced through.

Your HMRC payments

After the result, FLYNQD lists the payments the document shows: the balancing payment, payments on account (or a statement that none are due), the tax year each relates to, its due date and amount, and the line it came from. Payments sharing a due date are grouped, for example “31 January 2027: balancing payment and first payment on account”.

Each value is marked as from the document, calculated by FLYNQD under HMRC's rules, or corrected by you. FLYNQD never invents a date or amount it couldn't read. Where a balancing payment depends on payments already made, its amount is left blank rather than guessed.

A tax calculation (SA302) is not a statement of what you still owe. It shows what was due, not whether it has since been paid. Only a statement of account or your HMRC online account shows the current balance and payments already made, and FLYNQD never assumes an old payment is still outstanding.

You can confirm, correct or exclude each payment. A correction keeps the document's own figure next to yours. Confirmations here aren't saved and don't change your plan, and past dates never become reminders.

For the anonymised 2023/24 reference, FLYNQD reads £53.00 Income Tax, owed by 31 January 2025 (a past date), and no payments on account for 2024/25 because the tax was under £1,000.

Privacy and what happens to your document

The file is read in your browser. It isn't uploaded, saved to your plan, stored on this device or shared with anyone, including advisers.

Reference numbers such as your UTR and National Insurance number are removed from the text FLYNQD keeps while you review.

Everything is discarded when you press “Clear uploaded information”, switch person or tax year, or leave or reload the page. Checking a document never changes your plan or the figures you've entered.

To try it out, use the fictional sample documents on the Tax page, or a redacted copy. You don't need an account. This is a checking aid, not advice or a filing tool; HMRC's calculation is the one that counts.

What FLYNQD doesn't model yet

Figures from a document can't yet be saved into your plan. Scanned documents, other years, Scottish taxpayers, sharing with an adviser (FLYNQD Pro), client uploads (FLYNQD Light), amended calculations, adding payments to your forecast, payment reminders, marking a payment as paid, and payment workflows in FLYNQD Pro and Light are planned and not available.

Explore in your plan

• See your tax estimate

Related guides

• Checking your tax against HMRC's figures
• Calendar years, tax years and when tax is paid
• Capital Gains Tax: gains, losses and rates
• Tax in retirement