Gather your HMRC references, income statements, business or rental records, expense evidence and details of relevant pensions, donations, gains and loans. Use the tax year the return covers. Tell the accountant what is missing rather than waiting for a perfect folder.
Core documents most people should gather
- National Insurance number and Unique Taxpayer Reference (UTR) if you have one
- P60 / P45 / P11D where you also had employment
- Bank statements covering the tax year
- Records of other untaxed income you must report
If you are self-employed or freelancing
- Sales invoices and payment records (turnover)
- Expense receipts and bills that are wholly and exclusively for business
- Mileage or travel logs if you claim them
- Home-as-office workings if relevant
- Details of any stock, equipment or capital purchases
HMRC expects you to keep business records. Digital copies are fine if they are clear and complete.
If you have rental income
- Rent received (statements from agents help)
- Allowable property expenses (repairs, insurance, agent fees, and similar)
- Mortgage interest information where it affects your property calculations
- Dates properties were let, empty or personally used
Other common extras
- Dividend vouchers or broker summaries
- Bank / building society interest certificates
- Capital gains information if you disposed of assets
- Pension contribution records
- Charitable donation evidence for Gift Aid
- Student loan plan details if repayments interact with your return
Example
Alex freelances and lets one flat. Before using TaxSimba, Alex exports business bank CSV files, saves PDF invoices, downloads the letting agent’s annual statement, and photographs repair receipts. The accountant can prepare the return from that pack instead of chasing missing items in January.
Common mistake
Keeping only the “big” invoices and losing small recurring costs (software, phone, insurance). Those small items add up, and without evidence they are hard to support if HMRC asks questions.
If you already filed and then find missing documents that change the figures, use HMRC’s amendment process rather than hoping the gap never matters.
Build your pack
- List your income types for the tax year.
- Create a simple folder (digital is fine) per category.
- Note gaps early. Do not discover them on 30 January.
- If you want help, start the Self Assessment service and upload as you go.
Mark a missing document with an owner
Illustrative preparation example.
A P60 is ready, one rental statement is missing and the savings account has not been checked. Send the available records with a short gap list. Name who will obtain each missing item and when, instead of sending a folder that appears complete.
Check: Does your cover sheet identify missing records across every income source?
| Check | Practical action |
|---|---|
| Income-source list | List every relevant source before sorting documents. |
| Period coverage | Check start and end dates on each statement. |
| Missing evidence | Record who will obtain it and by when. |
Do bank statements explain every payment?
Not always. Keep invoices, statements and explanations for transfers, private spending and unusual transactions.
Should I send only documents showing income?
Include relevant expense, tax-deducted and other evidence as well. The exact pack depends on your circumstances.
Download a checklist for this guide
- Income sources for the tax year
- PAYE and tax-deducted documents
- Business or property supporting evidence
- Statement coverage and missing records
- Named owner and date for each gap