What documentation will UK taxpayers need to support Self Assessment submissions in 2024/25?

Introduction

Self Assessment can feel like a yearly admin marathon: gather information, make sense of it, check it, and submit it on time. For the 2024/25 tax year (running from 6 April 2024 to 5 April 2025), the key to a smooth Self Assessment submission is having the right documentation to back up the figures you put on your return. Even if you use software, an accountant, or HMRC’s online service, the underlying requirement stays the same: your numbers must be supported by records that are accurate, complete, and retained for the appropriate period.

This article sets out, in practical terms, what documentation UK taxpayers typically need to support their Self Assessment submissions for 2024/25. It’s written to help a wide range of taxpayers, including sole traders, landlords, company directors, partners in partnerships, higher earners, and anyone with more complex tax affairs. It also covers supporting documents for common reliefs and claims, so you can reduce the risk of errors and make it easier to respond if HMRC asks questions later.

Start with the basics: core identity and personal information

Before you even get into income and expenses, you’ll want to have a tidy set of basic details. These aren’t “evidence” in the same way as receipts, but they help ensure your return is correctly linked to you and that you complete the right sections.

Typical basics to have to hand include your National Insurance number, your Unique Taxpayer Reference (UTR) if you’re registered for Self Assessment, your current address and any address changes during the year, and details of any name changes. If you have a Government Gateway user ID and password for online filing, keep those secure and accessible. If you use an accountant or tax agent, ensure they have the right authorisation in place and that you can provide them with the relevant documents promptly.

Employment income: what you need if you were an employee or director

If you were employed at any point in 2024/25, or you were a company director receiving salary, you’ll need documentation that supports the pay and tax withheld through PAYE. The anchor document is usually your P60 from the end of the tax year, which summarises total pay and tax deducted. If you left a job during the year, a P45 from that employer helps show your pay and tax up to leaving date.

You should also keep your payslips (especially the final payslip of the tax year), as these can evidence pay, tax, National Insurance, student loan deductions, and any salary sacrifice arrangements. If you received benefits-in-kind (for example private medical insurance, company car, or other taxable benefits), the employer may provide details through payroll or via separate benefit statements. Depending on how your employer reports benefits, you may also have a P11D or a payrolled benefits summary.

If you incurred allowable employment expenses and intend to claim tax relief, keep evidence such as receipts, invoices, mileage logs (with dates, destinations, and business purpose), and documentation for professional fees or subscriptions if applicable. If you work from home and claim a proportion of household costs, keep utility bills and a reasonable basis for the apportionment, or evidence if you claim a flat-rate allowance.

Pensions: contributions, pension income, and lump sums

Pensions can show up in Self Assessment in multiple ways: contributions that attract relief, pension income you’ve received, and sometimes lump sums or drawdown. The documentation you need depends on what happened in the year.

If you made personal pension contributions, keep pension provider statements and contribution confirmations. For “relief at source” contributions (common for personal pensions), documentation should show the amount you paid and the grossed-up amount (including basic-rate relief added by the provider). For pension schemes where relief is given through your payslip (net pay arrangements), keep payslips and end-of-year summaries showing contributions. If you made contributions to more than one pension, keep records for each provider.

If you received pension income, keep the relevant pension statements and any forms showing tax deducted. For annuities, drawdown payments, or pension income paid under PAYE, documents similar to payslips may be issued. For State Pension, you may have a statement or online record showing the amount paid during the tax year. If you took taxable lump sums or had pension flexibility events, keep provider documentation that describes the payments and any tax withheld.

Self-employment: records for sole traders and freelancers

For sole traders and freelancers, the most important “category” of documentation is your business records. HMRC expects you to keep records sufficient to produce accurate accounts. In practice, that means evidence of all business income and all allowable business expenses, and a clear separation between personal and business where possible.

For income, keep sales invoices, receipts, till rolls (if relevant), bank statements showing customer payments, and any platform statements if you work through online marketplaces or payment processors. If you receive income in cash, keep daily or weekly takings records and a log showing how totals are calculated. If you have multiple income streams (services, product sales, affiliate income, royalties), keep separate records that clearly show amounts and dates.

For expenses, keep supplier invoices, receipts, and bank/credit card statements. Typical expense categories include travel and subsistence, office costs, phone and internet, insurance, advertising and marketing, professional fees, software subscriptions, and training costs (where allowable). If you use a vehicle for business, keep mileage logs and receipts for fuel and maintenance if claiming actual costs. If you work from home, keep household bills and a sensible method for apportioning business use, or record your use of simplified expenses if applicable.

If you bought equipment or other assets for your business, keep purchase invoices and documentation for capital allowances, including dates, amounts, and details of what was purchased. If you sold business assets, keep sale documentation as it may affect capital allowances or capital gains. If your business uses stock, keep purchase records, stock counts, and a method for valuing closing stock.

For taxpayers using accounting software, keep backups or exports and ensure you can produce underlying receipts if requested. Digital records are usually fine, but they should be legible, complete, and retrievable. For anyone using Making Tax Digital-compatible tools for VAT (where relevant), ensure your VAT records and submissions align with your Self Assessment accounting records.

Partnership income: what partners should keep

If you are a partner in a partnership, you will usually receive a partnership statement showing your share of the partnership’s profits, losses, and other allocated items. Keep the partnership statement, accounts, and any documents explaining the allocations. You may also need records of any drawings, capital introduced, and changes in your partnership interest if relevant.

Where the partnership includes different profit-sharing ratios for different types of income, or changes during the year, keep documentation showing how your share was calculated and when changes took effect. This helps ensure your return matches the partnership return and reduces the chance of mismatches that can lead to queries.

Rental income: landlords and property owners

Landlords need records that support rental income and allowable deductions. Keep tenancy agreements, rent schedules, and bank statements showing rent received. If a letting agent manages the property, keep agent statements, annual summaries, and details of fees deducted. If you have multiple properties, keep records for each one separately to help with accuracy and any future analysis.

For expenses, keep invoices and receipts for repairs and maintenance, replacement of domestic items (where the rules apply), property insurance, service charges, ground rent (if applicable), letting agent fees, and utilities paid by the landlord. For mileage or travel expenses relating to property management, keep a mileage log and evidence of journeys and purpose. If you pay for professional services (for example legal fees for tenancy agreements or accountancy fees related to property income), keep invoices and engagement letters where helpful.

Mortgage interest and other finance costs for residential property are subject to specific rules and are generally handled through a tax credit rather than a full deduction. Keep annual mortgage statements and lender interest certificates. If you have other finance arrangements (secured loans, bridging finance), keep the agreements and interest statements. For commercial property, the treatment may differ, so documentation remains essential.

If you furnished a property that qualifies for different rules (for example, certain furnished holiday letting rules in some contexts), keep booking records, occupancy logs, and evidence supporting any specific claims or classifications. Even if you use an agent or platform, retain the underlying statements that show income and fees.

Savings interest and bank accounts

Many taxpayers overlook savings interest because banks often pay it “net” without withholding tax, and because it can be relatively small. For Self Assessment, however, you may need to report taxable interest, especially if your overall income level makes it relevant.

Keep annual bank and building society interest statements, savings account summaries, and any tax certificates provided. If you have multiple accounts, create a list of accounts and the interest received from each during 2024/25. If you receive interest from peer-to-peer lending, keep platform statements showing interest, fees, and any bad debt relief or losses if applicable under the platform’s reporting.

For offshore interest or foreign bank accounts, keep statements showing interest credited, currency amounts, exchange rates used (or a consistent method), and any foreign tax withheld. Clear documentation is particularly important here because the reporting can be more complex.

Dividends and shares: documentation for investors

If you hold shares, you may receive dividends that need to be reported depending on your circumstances. Keep dividend vouchers, broker statements, and annual tax summaries from investment platforms. If you hold shares through nominee accounts, ensure you can identify dividends received and the dates paid. For those with multiple portfolios or brokers, consolidate records so you can report accurately.

If you hold unit trusts, OEICs, or other collective investments, you may receive distributions rather than straightforward dividends. Keep distribution statements and fund reports, as they can show the split between dividend-type income and interest-type income depending on the fund.

If you are a company owner receiving dividends from your own limited company, keep board minutes or dividend vouchers, dates of declaration and payment, and evidence of payment (bank statements). Ensure the dividend is properly documented as a dividend and not confused with salary, loans, or expense reimbursements. The supporting paperwork matters not just for your personal return but also for corporate governance and accounting.

Capital gains: selling property, shares, and other assets

Capital Gains Tax (CGT) documentation can be the difference between a straightforward calculation and a stressful reconstruction exercise. If you disposed of assets in 2024/25 (sold shares, sold a second property, sold cryptoassets, gifted assets, or transferred assets), keep records from acquisition through to disposal.

For property disposals, keep purchase completion statements, sale completion statements, legal fees invoices, estate agent fees, and evidence of capital improvements (for example, extensions, structural renovations, or major upgrades). Distinguish between repairs (generally an income expense for property) and improvements (generally relevant to CGT) by keeping clear invoices and project documentation. If the property was your main residence for some or all of the period, keep evidence of occupation dates and any periods of letting, as these can affect reliefs and calculations.

For share disposals, keep broker contract notes, statements showing acquisition costs, disposal proceeds, and fees/commissions. For shares acquired in multiple tranches, you need records to apply pooling rules correctly. If you received shares through employee share schemes, keep scheme documentation, award letters, and vesting statements, as the tax and CGT base cost can differ based on the scheme and tax paid.

For other assets (antiques, collectibles, business assets), keep purchase receipts, valuations (where relevant), sale receipts, and evidence of costs incurred to buy, sell, or improve the asset. If valuations are needed because you gifted an asset or transferred it to a connected person, keep valuation reports and correspondence showing how the value was determined.

Cryptoassets: exchanges, wallets, and transaction histories

Cryptoasset reporting has become increasingly relevant for Self Assessment. If you have bought, sold, swapped, gifted, or otherwise disposed of cryptoassets in 2024/25, you need documentation that supports your transaction history.

Keep exchange statements, CSV exports of transactions, and records of wallet addresses if you self-custody. You should also keep evidence of transfers between your own wallets and exchanges, so you can show they were not disposals but movements. Record transaction dates and times, quantities, GBP values at the time of transaction (using a consistent method), fees, and the nature of each transaction (buy, sell, swap, spend, receive).

For staking rewards, airdrops, mining income, or other crypto-related receipts, keep platform statements and logs showing amounts received and dates. The tax treatment can differ depending on the facts, so robust documentation is essential. If you use crypto tax software, keep the reports and ensure they can be reconciled to source data.

Foreign income and overseas assets

If you have foreign income—such as overseas employment income, foreign rental income, overseas pensions, dividends from foreign companies, or interest from foreign banks—you will need thorough supporting documentation. Keep foreign payslips, tax certificates, pension statements, rental accounts, and bank statements.

Where foreign tax has been withheld, keep evidence of the tax deducted and any official certificates. If you intend to claim Foreign Tax Credit Relief, documentation supporting the foreign tax paid is crucial. You should also keep a clear record of currency conversions used. Consistency matters: pick a reasonable approach (for example, using official exchange rates for relevant dates or an average rate where appropriate) and keep evidence of the rates or calculations used.

If you have overseas assets or are unsure whether certain offshore matters need to be declared, it’s prudent to keep organised records and seek professional advice. The complexity can rise quickly, and the documentation burden tends to be higher than for purely UK-based income.

Student loans and postgraduate loans

If you have student loan or postgraduate loan obligations, Self Assessment can be involved in calculating repayments when you have self-employment or other non-PAYE income. Keep payslips showing deductions made through PAYE and any end-of-year summaries. This helps you avoid double-counting or misunderstanding what has already been collected.

If you have correspondence about your loan plan type or changes in status, keep it. The plan type can affect thresholds and repayment calculations. If you believe repayments have been calculated incorrectly, having documentation to show deductions and income sources can help resolve issues faster.

Child Benefit and the High Income Child Benefit Charge

If you or your partner received Child Benefit and your income is above certain levels, you may need to account for the High Income Child Benefit Charge through Self Assessment. Keep Child Benefit award letters and any statements showing payments received during the tax year. Also keep evidence of any election to stop payments while keeping the claim open, if that applies to your circumstances.

Because the charge depends on income, your broader income documentation (employment, self-employment, dividends, interest, etc.) effectively becomes supporting evidence for calculating whether a charge applies and how much. Good records help you calculate accurately and avoid unpleasant surprises.

Gift Aid and charitable donations

Gift Aid can increase the value of charitable donations and can also affect higher-rate tax relief calculations. Keep donation receipts, confirmation emails, charity statements, and bank statements showing payments. For regular donations, an annual summary from the charity can be very helpful.

If you made donations of shares, land, or property, keep documentation showing the nature of the gift, the date, and the value or costs involved. For non-cash gifts, keep correspondence with the charity and any valuation evidence where relevant. If you are claiming tax relief on professional subscriptions or donations in other contexts, keep evidence showing eligibility and amounts.

Marriage Allowance and other personal tax matters

Some personal tax claims and elections may interact with Self Assessment. For example, if you are involved with Marriage Allowance (either transferring or receiving an allowance), keep confirmation of the claim and any correspondence. Although much of this is handled through HMRC systems, having your own records reduces confusion if circumstances changed during the year.

Other personal circumstances can affect tax, such as changes in residency, changes to your domicile status (where relevant), or changes in family situation. Keep key documents that show timelines and facts: travel records, employment contracts, tenancy agreements, and other items that establish where you lived and worked. For complex residency questions, records of days in and out of the UK can be particularly important.

Claiming expenses and reliefs: what evidence typically supports them

Self Assessment isn’t just about reporting income; it’s also where you may claim reliefs and deductions. HMRC expects you to be able to substantiate claims, so it helps to understand what “good evidence” looks like for common categories.

Professional fees and subscriptions: Keep membership invoices, proof of payment, and evidence that the organisation is relevant to your profession. If the claim depends on the subscription being to an approved body or being wholly and exclusively for work, keep documentation that supports that link.

Use of home: Keep household bills (electricity, gas, internet, council tax where relevant), mortgage interest statements or rent statements, and a method for apportioning business use. If using a flat-rate or simplified method, keep your workings and the basis for the claim (for example, number of hours worked from home).

Business travel: Keep mileage logs (date, start and end points, miles, business reason), receipts for parking and tolls, and tickets for public transport. For overnight trips, keep accommodation invoices and a record showing the business purpose.

Training and education: Keep invoices and course details that show the training relates to maintaining or improving existing skills rather than acquiring entirely new qualifications for a new trade. Evidence of relevance can help if there’s any doubt.

Capital allowances: Keep purchase invoices, proof of payment, and details of the assets. If you’re claiming allowances on equipment used partly for personal reasons, keep a reasonable basis for any business-use apportionment.

Loss relief claims: If you are claiming relief for trading losses, keep accounts, supporting documents, and clear calculations showing the loss and how it is applied. Loss relief can be scrutinised, so ensure your records are especially tidy.

Company directors and owner-managers: salary, dividends, and loans

Directors and owner-managers of limited companies often have a mix of salary, dividends, and other transactions. To support your Self Assessment, keep documentation for each stream and make sure it aligns with company accounts and payroll filings.

For salary, keep P60s, payslips, and any payroll summaries. For dividends, keep dividend vouchers and supporting corporate documentation such as board minutes approving dividends. Ensure the dividend amounts match the company’s records and that dividends were lawful (for example, supported by distributable reserves). Even if you’re not required to submit company documents with your personal return, inconsistencies can cause complications later.

If you borrowed money from your company or had a director’s loan account balance, keep records showing amounts borrowed, repayments, interest charged (if any), and dates. While the main tax consequences may fall within the company, director-level implications and the overall coherence of records matter.

Benefits, redundancy, and termination payments

If you received redundancy pay or termination payments, keep documentation from your employer explaining the amounts and how they were taxed. Termination packages can include multiple components (for example, contractual pay, payment in lieu of notice, ex-gratia sums), and the tax treatment can vary. Supporting paperwork makes it easier to report correctly and to challenge errors if something doesn’t look right.

If you received taxable benefits, keep any employer statements, benefit summaries, and evidence of how benefits were valued. For company cars, keep P11D details or payrolled benefit information, plus any evidence of employee contributions that reduce taxable value.

Interest and charges: pension annual allowance, high income issues, and other complexities

Some taxpayers face additional complications such as pension annual allowance issues, tapered annual allowance considerations, or unexpected tax charges. If you think you might be affected, keep all pension contribution statements, any “pension savings statements” from your scheme, and calculations of adjusted and threshold income if you or your adviser prepares them.

If a pension scheme paid an annual allowance charge on your behalf (often referred to as “scheme pays”), keep the election documentation and scheme confirmations. These situations are document-heavy, and good records prevent costly misunderstandings.

Property transactions and one-off life events

One-off life events often create tax complexity: selling a second home, receiving an inheritance, setting up a trust, getting married or divorced, or receiving a settlement. While not all such events will require special reporting on Self Assessment, many do, and they often involve significant sums.

For property transactions, keep conveyancing files, completion statements, and evidence of costs. For inheritances, keep probate documentation, valuations, and correspondence showing what you received and when. If you received income from an estate (for example, estate interest or dividends), keep statements from executors or administrators.

For trusts, keep trust statements, distribution vouchers, and correspondence that shows the nature of the distribution (income versus capital) and any tax credits. If you’re a trustee, the record-keeping requirements can be more extensive.

Records for tax credits, pension credits, and other benefits

If you receive certain benefits or credits that interact with income reporting or if you need to evidence household income, keep award notices and correspondence. While many benefits are administered outside Self Assessment, it can still be helpful to keep a coherent set of records, particularly if your income changes materially and you need to reconcile figures across systems.

How long should you keep Self Assessment records?

It’s not enough to gather documents for filing; you also need to retain them for the required period. In general, taxpayers should keep Self Assessment records long enough to support the return if questions arise later. For business records, the retention period is often longer than many people expect, and it can differ depending on whether you are self-employed, a landlord, or filing as an individual with simpler circumstances.

As a practical rule, keep records for several years after the relevant filing deadline, and longer if your affairs are complex, if you have ongoing capital gains base cost records, or if you anticipate disputes. For example, records supporting the purchase cost of an asset sold in a later year should be retained until after the asset is disposed of and the tax position is settled, because you may need those documents years after the original purchase.

Digital storage can make retention easier. Scan paper receipts, keep them organised by tax year, and ensure files are backed up securely. The goal is simple: if you need to produce evidence later, you can do so quickly and confidently.

Practical organisation: building a “Self Assessment evidence pack” for 2024/25

A helpful approach is to build a structured “evidence pack” for the year, either as folders in cloud storage or as a physical file with clearly labelled sections. This helps you avoid last-minute scrambling and makes it easier to work with an accountant.

Consider using a structure like:

1) Employment: P60, P45s, payslips, benefits summaries, expense receipts.

2) Self-employment: income invoices, expense receipts, bank statements, mileage logs, asset purchases, software reports.

3) Property: tenancy agreements, rent statements, agent statements, mortgage interest statements, repairs invoices.

4) Investments: bank interest statements, dividend vouchers, broker tax summary, fund distribution statements.

5) Capital gains: purchase/sale documentation, contract notes, fees, improvement costs, valuations.

6) Pensions and reliefs: pension contribution statements, Gift Aid receipts, subscription invoices, relief calculations.

7) Overseas: foreign statements, tax certificates, exchange rate workings.

Within each folder, naming conventions matter. For example: “2024-07-15_SupplierName_Invoice_£123.45.pdf” or “2025-03_Broker_Statement.pdf”. A small amount of tidiness now can save hours later.

Common mistakes caused by missing documentation

Understanding what goes wrong can help you focus on the most important records. Missing documentation often leads to these problems:

Underreporting income: forgetting interest from a small savings account, missing dividends, or failing to include platform income.

Overclaiming expenses: claiming items without adequate evidence, mixing personal and business costs, or misunderstanding what is allowable.

Incorrect treatment of property costs: confusing repairs with improvements, mishandling finance costs, or misallocating expenses between properties.

Inaccurate CGT calculations: missing acquisition costs, not accounting for fees, or failing to apply the correct share pooling approach.

Inconsistent figures across documents: dividends not matching company records, wages not matching PAYE summaries, or mismatched totals between accounts and bank statements.

Most of these issues are avoidable if you treat documentation as part of the tax process rather than an afterthought.

What HMRC might ask for if they check your return

If HMRC makes enquiries or requests further information, they generally want to see evidence supporting specific figures on your return. That could include invoices and receipts for expenses, bank statements showing income received, calculations for apportionments (for example home office or mixed-use assets), and statements from third parties such as brokers, pension providers, or letting agents.

HMRC may also ask for explanations of unusual items: a large one-off expense, a sudden drop in profit, significant losses claimed, or substantial capital gains. If you can respond with clear documentation and a short explanation, queries are typically easier to resolve.

When professional advice is especially helpful

Many people can complete Self Assessment themselves with careful record-keeping. However, there are situations where professional advice can be valuable, especially where documentation needs to be interpreted correctly. Examples include: complex capital gains, overseas income, residency questions, cryptoactivity with high transaction volumes, pension annual allowance issues, and ownership structures involving trusts or multiple parties.

Even if you use an accountant, you still benefit from having your own documentation organised. Professional advice works best when your records are complete and you can provide them quickly.

Final checklist for 2024/25: documents to gather before you start your return