Prepare the sole-trade income and costs for 6 April 2025 to 5 April 2026, using the correct accounting method. Include any PAYE income and tax already paid, such as CIS deductions. Tell the accountant about the whole personal tax position, not just the business bank account.
Income and sales evidence
- Invoices or sales reports for the tax year (6 April 2025 to 5 April 2026)
- Bank statements for the business account (or highlighted personal-account business lines)
- Platform payouts (marketplaces, card readers) reconciled to invoices
- CIS statements if you are a subcontractor
- Any tips, grants or other trading receipts
Business expenses worth sorting early
Group costs the way your accountant will ask for them: stock or materials, subcontractors, premises, vehicle/travel, office costs, professional fees, insurance, phone/internet used for the trade, and capital purchases that may need capital allowances. Private spending mixed into the same account needs a clear split. “I’ll remember in January” is how allowable claims get lost.
A concrete prep example
Maya is a freelance photographer. For 2025 to 2026 she has invoices totalling £42,600, equipment hire and props of £3,150, software subscriptions of £480, train travel to shoots of £920, and a new camera body costing £1,800 that may need capital-allowance treatment rather than a simple expense. She exports bank CSV files and keeps PDF invoices in one folder labelled by month. That pack is enough for an accountant to draft the trade pages without reconstructing the year from memory.
Other income and the rest of the return
Sole-trader profit is rarely the whole story. Note employment income, taxable benefits, dividends, savings interest, rental income, pension contributions, and student loan indicators. Payments on account from the previous year also affect what you pay by 31 January. See payments on account explained.
Accountant workflow, approval and deadlines
Online return and balancing payment for 2025 to 2026: 31 January 2027. Paper deadline: 31 October 2026. If you still need to register or reactivate Self Assessment for this year, check the 5 October 2026 notification date.
TaxSimba’s Self Assessment service is accountant-led: you supply the records, an accountant prepares the return, you approve, then it is filed. We do not sell DIY filing software or promise a fixed tax saving.
Check the home nation used for your tax calculation
Tell the accountant whether you live in England, Scotland, Wales or Northern Ireland, and about any moves during the tax year. Scottish rates differ for wages, pensions and most other taxable income; savings and dividends use UK rules. Welsh rates are set separately. Use the rules for the relevant year and your actual taxpayer status.
See Scottish Income Tax and Welsh Income Tax. These differences do not make a London address or an England-only earnings example appropriate for everyone.
Check the trade and personal return together
Illustrative preparation example.
Your business records reconcile, but a P45 and CIS statement are outside the folder. Add those documents to the personal-return pack. A correct trading-profit figure is only part of a return that must also reflect other relevant income and tax already deducted.
Check: What information belongs on the personal return beyond the business accounts?
| Check | Practical action |
|---|---|
| Do recorded sales include cash and platform fees? | Reconcile gross customer receipts to net payouts without counting transfers twice. |
| Which accounting basis applies? | Confirm cash basis or traditional accounting before allocating dates and equipment costs. |
| Is the personal return complete? | Include employment, savings, property and relevant relief information as well as the trade. |
Is the business bank statement enough?
It is useful evidence, but it may omit cash, hide platform deductions or include private transfers. Supply the sales and expense records behind it.
Does every equipment purchase need capital allowances?
No. Treatment depends on the asset and accounting basis. Keep the invoice and business-use details so the appropriate rules can be applied.
Download a checklist for this guide
- Confirm the tax year and accounting basis.
- Reconcile bank, cash and platform sales.
- Group expenses and mark private-use shares.
- List equipment purchases and disposals.
- Gather other income, reliefs and prior payments.