More than most people expect. An accountant can usually prepare an overdue return from bank and card statements, payment-platform reports, copies of invoices held by customers and suppliers, earlier returns and the income HMRC already holds for you. Missing receipts change how a figure is documented. They do not, on their own, stop a return being prepared.
This guide covers records that were lost, destroyed or never kept, whether through a fire, a flood, a theft, a failed laptop or simply a gap in the paperwork. Where the documents still exist and only need sorting, the work is closer to turning a box of receipts into filed returns. Estimates also deserve care this year: in early 2026 HMRC wrote to some people whose 2024 to 2025 returns included provisional or round-sum figures, asking them to check and correct them.
Which Records Can an Accountant Use?
Start with the sources that sit outside your own files, because other organisations keep copies. The table shows what each source can establish and where it usually falls short, so you know which gaps will still need an explanation.
| Source | What it can show | Where it falls short |
|---|---|---|
| Bank and card statements | Money received and paid, with dates and payees | Does not show what was bought, or whether a credit was business income |
| Payment platform and marketplace reports | Sales and fees routed through the platform | Calendar-year reports need splitting into tax years |
| Copy invoices from customers and suppliers | The detail behind individual sales and purchases | Depends on the other party keeping and supplying them |
| Your HMRC personal tax account | Income from work and Income Tax paid in the previous 5 years, and your UTR | Does not hold self-employment or rental figures you never reported |
| Earlier returns and accountant files | How figures were treated before and which years are complete | Only covers years that were filed |
| Diaries, emails, booking apps and mileage logs | Dates of jobs, customers and journeys | Rarely give amounts on their own |
Recovering Bank, Invoice and Platform Records
Ask each bank for statements covering every tax year you need, from 6 April to 5 April, including any personal account the business used. Banks set their own rules on how far back they can go and whether they charge, so ask before assuming a period is lost. Note the date of each request so the gap is documented even while you wait.
Digital platforms have reported sellers’ income to HMRC since 1 January 2024. HMRC’s guidance on selling through digital platforms says operators must give you a copy of what they reported, showing calendar-year earnings less fees and commission, split into quarters. That copy is a useful check, but HMRC also says it does not replace your business records, and its January to March figures belong to the previous tax year.
For sales and purchases, ask customers and suppliers for copies of invoices they issued or received. Keep the copy they send and the request. Do not create a replacement invoice yourself or alter an old one: a reconstructed figure should be presented as reconstructed. Employment income and tax deducted for recent years can be checked in your personal tax account.
What to Send an Accountant When Records Are Incomplete
Send what you have, together with a clear list of what is missing. An accountant can only explain the work needed once they can see the shape of each year, and a partial set sent early is more useful than a complete set that never arrives.
- The tax years you think are outstanding, with any notice to file, penalty letter or deadline.
- Every statement, report and invoice you have recovered, labelled by year and source.
- A list of gaps: the missing period, the account or platform, and who you have asked for a copy.
- A short note of what happened to the records, with any incident, police or insurance reference if they were destroyed or stolen.
- Details of cash income or costs that never passed through a bank account, and how you know about them.
- Copies of earlier returns, or the name of the previous accountant who prepared them.
Estimated Figures, Provisional Figures and Their Limits
HMRC’s guidance on lost records says that if you cannot replace records, you must do your best to provide figures, and tell HMRC when you file if you are using estimated or provisional figures. An estimated figure is your best guess where the actual amount will not become available. A provisional figure is a temporary estimate while you wait for the actual one, and you must submit the actual figure when you have it.
Build each estimate from evidence: an average of months where statements survive, supplier records for a known cost, or a mileage figure rebuilt from dated jobs. Write the method down. The Low Incomes Tax Reform Group’s summary of HMRC’s 2026 letters explains that a provisional figure has to be replaced through an amendment, and that ignoring the follow-up can lead to an enquiry.
An accountant cannot promise HMRC will accept an estimate
HMRC does not approve estimates in advance. What an accountant can do is make sure each figure is flagged correctly, based on a stated method and supported by the evidence you have. A guessed round number with no working is the hardest figure to defend.
Records Reconstruction Checklist
- 1List each outstanding tax year and note any HMRC deadline for it.
- 2For each year, list every bank account, card, platform and other income source that may hold records.
- 3Request missing statements, platform reports and copy invoices, and keep a dated log of each request and reply.
- 4Go through bank credits line by line, separating business income from transfers, refunds and personal money.
- 5Mark every figure as confirmed, estimated or provisional, with the document or method behind it.
- 6Write a short method note for each estimate, including what is missing and why it cannot be recovered.
- 7Agree with your accountant how estimates will be flagged on the return, and when provisional figures will be replaced.
- 8Keep the reconstruction file with the return once it is filed.
HMRC’s record-keeping rules still apply to a reconstruction. Records are normally kept for at least 5 years after the 31 January submission deadline, and a return sent more than 4 years after its deadline needs its records kept for 15 months after you send it.
Lost Records and Late-Filing Penalties
HMRC’s list of reasonable excuses includes a fire, flood or theft that prevented you from completing your return. It also says you must send the return as soon as you are able. An excuse of that kind can support an appeal for the period you were genuinely prevented from filing; it does not cover a delay after you could have started again, and it does not reduce the tax itself.
Keep the evidence of the event alongside the reconstruction, and note the date you were able to start rebuilding the figures. That timeline is what any appeal will be judged on.
Help With Returns Built From Incomplete Records
Our multiple-year returns service works through each missing year separately, records which figures are confirmed and which are estimated, and agrees the filing route with you. If only one return is overdue, our late tax return filing service starts from the records you have now. We will tell you what is still needed before quoting, and we cannot promise how HMRC will treat any estimate.