What Documents Do You Need for Your Self Assessment Tax Return?
Once you know you need to complete a Self Assessment tax return, the next question is usually:
What do I actually need to give my accountant?
For the 2025/26 tax year, covering 6 April 2025 to 5 April 2026, gathering your records in October can save a significant amount of time later.
HMRC’s own 2025/26 tax-return guidance lists documents including P60s, P45s, P11Ds, business records, bank statements, dividend information and pension contribution certificates among the information you may need. GOV.UK
You will not necessarily need everything below. What you need depends on where your income came from and what happened financially during the year.
Start with your employment documents
If you were employed during 2025/26, you may need your employment records.
These can include:
- P60 – summarises your pay and tax for the tax year
- P45 – provided when you leave an employment
- P11D – details certain taxable expenses and benefits provided by your employer
- Payslips
- PAYE Coding Notices where relevant
HMRC specifically identifies P60s, P11Ds, P45s, payslips and PAYE Coding Notices as documents that may be useful when completing a return. GOV.UK
If you changed jobs during the year, make sure you have information covering each employment.
If you’re self-employed
Sole traders generally need considerably more information because the return needs to establish the income and allowable expenses of the business.
HMRC requires self-employed people to keep records of:
- All sales and business income
- Business expenses
- VAT records if VAT registered
- PAYE records if they employ people
- Relevant personal income
HMRC says supporting evidence can include receipts, bank statements, sales invoices and bank slips. GOV.UK
Your accountant may therefore ask for items such as:
Sales records and invoices
These establish how much the business earned.
Business bank statements
Ideally, provide statements covering the entire relevant accounting period.
Purchase invoices and receipts
These support the costs being claimed.
Mileage records
These can be important where vehicle or mileage costs are being claimed.
Software records
If you use Xero, QuickBooks or another accounting platform, make sure it is up to date and that your accountant has the necessary access.
The aim is not simply to produce a pile of receipts. Your records need to allow the business’s income, expenses and profit to be established accurately.
What business expenses should you gather?
If you’re self-employed, collect evidence for legitimate business expenditure.
Depending on the business, that could include:
- Materials and stock
- Software
- Advertising
- Professional fees
- Insurance
- Telephone costs
- Internet costs
- Travel
- Business mileage
- Office costs
- Equipment
- Subcontractor costs
- Training
- Bank charges
Not every expense paid from a business account is automatically tax deductible.
Equally, paying for a genuine business expense personally does not necessarily mean it should be forgotten.
Give your accountant enough information to establish the correct treatment.
Don’t forget income paid outside your normal bank account
A common problem is assuming that the bank statement tells the whole story.
Perhaps customers paid through:
- PayPal
- Stripe
- SumUp
- Cash
- Another bank account
- An online marketplace
- A payment-processing platform
These transactions may still form part of your business income.
HMRC requires self-employed taxpayers to keep records of all sales and income, not simply the amounts that happened to reach one particular account. GOV.UK
If you receive rental income
Landlords should gather information covering both income and relevant property costs.
Depending on the property and circumstances, this could include:
- Rental statements
- Tenancy information
- Letting-agent statements
- Property-management fees
- Repairs and maintenance invoices
- Insurance
- Service charges
- Ground rent
- Utility costs you paid
- Relevant finance information
- Other property expenditure
If you use a letting agent, their annual statement can be a useful starting point.
However, don’t assume it contains every expense you paid personally.
What about Airbnb or short-term rental income?
You should also gather records where you earned money through short-term accommodation platforms.
Keep information showing:
- Gross booking income
- Platform charges
- Cleaning costs
- Property costs
- Other relevant expenditure
The tax treatment can depend on what you are renting and your circumstances, so provide the underlying figures rather than simply giving your accountant the amount left after the platform deducted its fees.
Savings interest
If you earned savings interest during 2025/26, gather the relevant bank and building-society information.
That could include:
- Annual interest statements
- Bank statements
- Savings-account summaries
- Interest certificates
HMRC specifically lists bank statements and building-society records among the documents that may be needed when preparing a return. GOV.UK
If you have several savings accounts, check all of them rather than just your main bank.
Dividend income
If you received dividends, gather evidence of the amounts paid.
This could include:
- Dividend vouchers
- Investment-platform tax summaries
- Broker statements
- Dividend records from your own limited company
HMRC’s return guidance specifically identifies dividend records and investment brokers’ schedules among the documents taxpayers may need. GOV.UK
For owner-managed companies, make sure the dividends you report personally agree with the company’s underlying dividend documentation.
Pension contributions
Personal pension contributions can affect your tax calculation.
Keep records showing contributions made during the tax year.
HMRC specifically includes personal pension contribution certificates among the documents taxpayers may need when completing the 2025/26 return. GOV.UK
This can be particularly important for higher-rate and additional-rate taxpayers because additional tax relief may need to be considered.
Don’t assume HMRC automatically has everything required to calculate your position correctly.
Gift Aid donations
If you made charitable donations under Gift Aid, keep a record of them.
Your accountant may ask:
- Which charities you donated to
- How much you donated
- When you made the donations
- Whether Gift Aid was claimed
Gift Aid can affect your tax calculation, particularly for higher-rate taxpayers.
A bank statement can help reconstruct donations if you have not maintained a separate record.
Capital gains
If you sold or disposed of investments or other chargeable assets, considerably more information may be required than simply the amount you received.
HMRC says records for Capital Gains Tax can include evidence showing:
- What you paid for the asset
- Additional acquisition or disposal costs
- What you received when disposing of it
- Relevant professional fees
- Improvement expenditure where applicable
- Contracts
- Valuations GOV.UK
For shares or investments, obtain the transaction history from your broker or investment platform.
For property, you may need older records from when the property was originally purchased.
Cryptocurrency transactions
If you bought, sold, exchanged or otherwise disposed of cryptoassets during the year, your accountant may need transaction records.
That can become difficult if you used several:
- Exchanges
- Wallets
- Platforms
- Cryptocurrencies
Do not provide only the current value of your portfolio.
Calculating gains can require the underlying transaction history.
Downloading this information while you still have access to the relevant accounts can prevent problems later.
Foreign income
If you received overseas income, gather the relevant records before completing your return.
Examples might include:
- Foreign bank interest
- Overseas dividends
- Foreign rental income
- Overseas pensions
- Foreign employment income
- Other overseas income
You may also need evidence of foreign tax already paid.
Foreign-income taxation can be complex, so provide your accountant with the original information rather than trying to decide yourself what is or is not taxable in the UK.
Student loan information
Tell your accountant if you have an outstanding:
- Student Loan
- Postgraduate Loan
This can affect the calculation made through Self Assessment.
If repayments have already been deducted from employment income, retain the relevant payroll records so these can be considered.
Child Benefit information
If the High Income Child Benefit Charge could apply, your accountant may need details of Child Benefit received and your wider circumstances.
Do not assume that because Child Benefit was paid to your partner it has no relevance to your own tax position.
If you are unsure, flag it when providing your Self Assessment information.
Do you need to send HMRC all your receipts?
Usually, no.
HMRC states that self-employed taxpayers do not send their business records with the return. They must instead keep them so they can calculate the return and provide evidence if HMRC asks for it. GOV.UK
HMRC’s 2025/26 return notes similarly tell taxpayers not to send receipts, accounts or other paperwork with the return unless requested. GOV.UK
If an accountant prepares your return, however, they may need to see relevant records to prepare accurate figures.
Digital records are fine
Your filing cabinet does not need to be overflowing with paper.
HMRC says records can generally be kept:
- On paper
- Digitally
- Within software such as bookkeeping software
The important thing is that they remain accurate, complete and readable. GOV.UK
A well-organised digital folder can therefore work perfectly well.
For example:
2025-26 Self Assessment
Then folders for:
Employment
Self-employment
Property
Savings
Dividends
Investments
Pensions
Other
That is considerably easier to work with than hundreds of screenshots scattered across your phone.
What if you’ve lost a receipt or statement?
Don’t automatically guess the number.
HMRC says you should try to obtain replacement records where possible, such as requesting duplicate statements from a bank or duplicate invoices from suppliers. GOV.UK
If records genuinely cannot be recreated, HMRC permits provisional or estimated figures in certain circumstances, but you must identify them appropriately on the return. GOV.UK
The better approach is therefore:
Reconstruct first. Estimate only where necessary.
How long should you keep Self Assessment records?
The answer depends on your circumstances.
For self-employed taxpayers, HMRC currently requires records to be retained for at least five years after the 31 January submission deadline for the relevant tax year. GOV.UK
Different retention periods can apply to people who are not in business, late returns and situations where HMRC has opened an enquiry. HMRC’s legal guidance states that non-business taxpayers generally retain the supporting documents for one year after the relevant 31 January deadline, subject to extensions for late returns or enquiries. GOV.UK
So don’t delete everything immediately after pressing submit.
A simple Self Assessment checklist
Before sending your information to your accountant, check whether you have covered each relevant category:
- Employment income
- Self-employed income
- Business expenses
- Property income
- Savings interest
- Dividends
- Pension contributions
- Gift Aid
- Capital gains
- Cryptoassets
- Foreign income
- Student loans
- Child Benefit
- Any other untaxed income
You will probably not need every category.
The objective is to make sure nothing relevant has been forgotten.
Why October is a good time to organise everything
The online Self Assessment deadline may not be until 31 January 2027, but that does not mean January is the best time to start.
HMRC explicitly notes that filing earlier allows you to find out what you owe sooner. GOV.UK
Preparing in October gives you time to:
- Find missing documents
- Request replacement statements
- Resolve bookkeeping problems
- Ask questions
- Calculate your liability
- Correct mistakes
- Budget for the tax payment
If you discover a missing document on 15 October, there is time to fix it.
If you discover it on 30 January, there isn’t much.
Frequently Asked Questions
What documents do I need for Self Assessment?
It depends on your circumstances, but common records include P60s, P45s, P11Ds, business records, bank statements, dividend information, investment records and pension contribution certificates. GOV.UK
Do I need bank statements?
They can be important evidence of income and expenditure. HMRC specifically identifies bank statements among records used to complete Self Assessment accurately. GOV.UK
Do I send my receipts to HMRC?
Normally not with the return. You should retain supporting records because HMRC can ask to see them. GOV.UK
What if I’ve lost my records?
Try to obtain replacements or reconstruct them. HMRC allows estimated or provisional figures in certain circumstances where records genuinely cannot be recreated, but these need to be identified appropriately. GOV.UK
Should I give my accountant everything?
Give your accountant the information relevant to your tax position. If you’re unsure whether something matters, it is generally better to flag it than silently leave it out.
When is the 2025/26 online return due?
The normal online Self Assessment filing deadline is 31 January 2027. HMRC also requires the resulting Self Assessment bill to be paid by 31 January. GOV.UK
Final thoughts
Getting your Self Assessment documents together doesn’t need to be complicated.
Start with one question:
Where did my money come from between 6 April 2025 and 5 April 2026?
Then work through each source and collect the records supporting it.
Doing this in October gives you several months to resolve anything missing and, crucially, find out how much tax you’re likely to owe before the January deadline arrives.
At Merranti Accounting, we help individuals, sole traders and business owners prepare their Self Assessment returns and make sure the relevant income, expenses and tax information are recorded correctly.
Written by Jack Smith MAAT
Senior Client Manager, Merranti Accounting
Jack is an AAT-qualified accountant with more than 12 years of experience supporting SMEs and owner-managed businesses. His work includes year-end accounts, management reporting, bookkeeping, VAT, tax planning, forecasting and practical financial advice.
