Sole traders
Business income and expenses where your circumstances require a Self Assessment return.
Self Assessment accountant in West London
Know what you need to report, what you can claim, and what you need to pay.
SV&Co prepares Self Assessment tax returns for sole traders, landlords, CIS subcontractors, company directors who need to file, and individuals with other taxable income or gains across Southall and West London.
Before you file your tax return
Four questions worth answering first.
Do I actually need a tax return?Check whether Self Assessment applies to your situation.
What is my taxable profit?Understand income, expenses and the figure HMRC taxes.
What expenses can I claim?See the common categories and where the rules need care.
Why is my January bill so high?Understand balancing payments and payments on account.
If you do not know the answers, the sections below explain them in plain English.
Start with your question
Choose what you want to understand.
You do not need to read the page in order. Jump directly to the issue that matters to you.
Useful before you contact usClear answers first. Professional review when you need it.
Self Assessment
Do I need to send a tax return?
See the common reasons people need to file and where HMRC's checker can help.
Check the position ProfitHow is self-employed profit worked out?
Understand the difference between business income, expenses and taxable profit.
Understand profit ExpensesWhat business expenses can I claim?
See common expense categories and why personal costs cannot simply be put through the business.
See expense rules Tax billWhy do I have payments on account?
Understand the January and July advance payments and why a first January bill can feel unexpectedly high.
Understand payments Making Tax DigitalDoes MTD for Income Tax apply to me?
MTD is already live for some sole traders and landlords. See the current thresholds and start dates.
Check MTDDo you need to file?
Self Assessment is needed for more than just self-employment.
HMRC has an official online checker. Where your position involves several sources of income, property, capital gains or an HMRC notice, we can review the position with you.
Landlords
Rental income, property expenses and other taxable income that needs reporting.
CIS subcontractors
Self-employed income, expenses and CIS tax already deducted by contractors.
Company directors
Directors do not automatically need a return simply because they are directors, but their wider tax circumstances may require one.
Capital gains or other income
Certain disposals, investment income or other taxable amounts can create a filing requirement.
HMRC has asked you to file
If HMRC issues a notice to file, do not ignore it. We can help review what is required.
2025 to 2026 return
Three dates to keep clear.
Filing early gives you more time to understand the bill and plan the cash rather than finding out in January.
5 Oct 2026Normal deadline to tell HMRC if you are newly required to file for 2025 to 2026.
31 Oct 2026Paper Self Assessment filing deadline for 2025 to 2026.
31 Jan 2027Online filing deadline and normal balancing payment deadline for 2025 to 2026.
Self-employed profit
Turnover is not the same as profit.
For a simple sole trader, you start with business income and deduct allowable business expenses. Tax rules can then affect the final taxable profit.
Business incomeSales, fees and other trading income.
Less allowable expensesBusiness costs that meet the tax rules.
Business profitThe amount left before personal Income Tax and National Insurance.
Taxable resultAdjusted where the tax rules require a different treatment.
Your bank balance is not your taxable profit.
Cash can move for many reasons, for example buying equipment, repaying borrowing, personal drawings or money introduced into the business. We prepare the tax position from the business records, not simply from the closing bank balance.
Allowable business expenses
Claim the right costs, not every cost.
HMRC lists common categories of allowable expenses. The important question is whether the cost is genuinely for the business and how any private element should be treated.
Common business costs
Depending on the business and accounting method, relevant expenses can include:
- Office costs and stationery.
- Business phone and software.
- Business travel costs.
- Staff and subcontractor costs.
- Stock and materials.
- Insurance and bank charges.
- Business premises costs.
- Professional fees.
What we checkWhether the expense is allowable, whether there is private use, and whether another tax treatment such as capital allowances is required.
Costs that need care
Some common areas need more than a receipt to decide the tax treatment.
- Cars, vans and mileage.
- Working from home.
- Meals and travel.
- Clothing.
- Equipment and larger purchases.
- Mixed personal and business costs.
- Interest and finance.
- Training and professional subscriptions.
What this gives youA tax return based on supportable business claims rather than guesswork.
Payments on account
Why can your first January tax payment feel much bigger than expected?
If HMRC requires payments on account, you can be paying the balance for the year just finished and an advance payment towards the next year's bill at the same time.
31 JanuaryBalancing payment for the previous tax year, plus the first payment on account for the next year.
31 JulySecond payment on account towards that next year's bill.
Payments on account are normally two equal instalments.
Each is generally half of the previous year's relevant Self Assessment liability. HMRC does not normally require them if the relevant tax is under £1,000, or if more than 80% of your tax was already collected outside Self Assessment.
Payments on account explainer
Enter a simple previous Self Assessment liability and tax already collected at source.
Making Tax Digital for Income Tax
MTD is already live for some sole traders and landlords.
If your qualifying income was over £50,000 for 2024 to 2025, you should have started using MTD for Income Tax from 6 April 2026. The threshold falls in later years.
MTD changes the way records are kept and updates are sent to HMRC. It does not mean that accurate bookkeeping or professional review becomes less important.
Who we help
Different Self Assessment clients need different support.
The tax return is the final output. The real work depends on where the income comes from and how good the underlying records are.
Sole traders
Accounts, allowable expenses, Income Tax, National Insurance, payments on account and MTD.
See how we help
- Prepare business income and expense figures.
- Review allowable expenses.
- Calculate taxable profit.
- Prepare and file the tax return.
- Explain tax and payments on account.
- Review MTD status.
OutcomeYou know what profit HMRC is taxing and what needs to be paid.
Landlords
Rental income, property expenses, other personal income, MTD and Capital Gains Tax issues.
See how we help
- Prepare rental income and expense schedules.
- Review finance-cost treatment.
- Include other relevant income.
- Review MTD qualifying income.
- Identify separate CGT reporting where relevant.
OutcomeYour property tax position is prepared consistently with the rest of your personal return.
CIS subcontractors
Self-employed accounts where contractors have already deducted CIS tax.
See how we help
- Review CIS deduction statements.
- Prepare business income and expenses.
- Claim relevant CIS deductions in the tax return.
- Explain any refund or tax still due.
OutcomeYour return reflects both the business profit and tax already deducted under CIS.
Individuals with several income sources
Employment, property, investments, overseas matters or other taxable income in one return.
See how we help
- Identify what needs reporting.
- Bring relevant income sources together.
- Review tax already deducted.
- Prepare the overall Self Assessment calculation.
OutcomeYou see the complete tax position rather than looking at each income source separately.
Late or disorganised records
For clients who have fallen behind or are unsure what HMRC needs.
See how we get things back on track
- Identify the tax years outstanding.
- Organise bank records and supporting information.
- Prioritise deadlines and HMRC correspondence.
- Prepare the missing return or accounts.
- Put a better record-keeping process in place.
OutcomeYou move from uncertainty to a clear list of what needs to be done first.
People considering a limited company
For sole traders who want to understand whether remaining self-employed or incorporating better suits their circumstances.
See what we review
- Current profit level.
- How much money you need personally.
- Administrative cost and complexity.
- VAT, payroll and company obligations.
- Tax is one factor, not the only factor.
OutcomeYou understand the practical differences before changing business structure.
What we do
Good Self Assessment starts with good records and clear explanations.
We do not want the tax return to feel like a black box. You should understand what has been reported and why the tax bill looks the way it does.
Organise the information
Bring the relevant records into one workable tax file.
- Business bank records.
- Income records.
- Rental schedules.
- CIS statements.
- Employment records.
- Investment information.
- Capital transactions.
- HMRC correspondence.
What this gives youA complete starting point before the tax return is prepared.
Prepare the taxable figures
Work out the figures that belong on the return rather than simply copying bank transactions.
- Self-employed profit.
- Allowable expenses.
- Rental profit.
- CIS deductions.
- Other taxable income.
- Relevant reliefs.
- Tax already deducted.
- Payments on account.
What this gives youA tax calculation based on the tax rules and the underlying records.
Explain the tax bill
Understand why the amount is due and which part relates to which year.
- Income Tax.
- Class 4 National Insurance.
- Balancing payment.
- First payment on account.
- Second payment on account.
- Tax already deducted.
- Refunds where applicable.
- Payment dates.
What this gives youYou can plan the cash instead of only seeing one unexplained number.
Prepare for the next year
Use the completed return to improve the next tax cycle.
- Review payments on account.
- Improve bookkeeping.
- Move to digital records.
- Prepare for MTD.
- Review business structure.
- Plan tax reserves.
- Discuss large transactions.
- Identify records to keep.
What this gives youLess pressure at the next deadline and better information during the year.
Simple tax tools
See why profit and the final tax bill are not the same thing.
These are educational estimates using current 2026 to 2027 standard England, Wales and Northern Ireland Income Tax bands and self-employed Class 4 National Insurance rates. They do not replace a full tax calculation.
Sole trader tax estimate
Enter an estimated annual self-employed taxable profit, assuming no other income.
Why this is only an estimate
Your actual Self Assessment can be affected by employment income, property, dividends, savings, pensions, student loans, losses, Marriage Allowance, High Income Child Benefit Charge, Capital Gains Tax and other factors.
Use it to understand the mechanics, not to decide what to pay HMRC.
The final tax position should come from the completed return and supporting records.
Self Assessment FAQs
Quick answers before you contact us.
What is the online filing deadline for the 2025 to 2026 tax return?
The online Self Assessment deadline is normally 31 January 2027. Any balancing payment normally due for that return is also due by 31 January.
Can I file before January?
Yes. The return can be submitted after the end of the tax year. Filing earlier can help you understand the tax bill and plan payment sooner.
What are payments on account?
They are advance payments towards the next Self Assessment bill. They are normally paid in two instalments on 31 January and 31 July where HMRC's conditions are met.
Can I claim every cost paid from my business bank account?
No. Paying an item from the business account does not automatically make it tax deductible. The expense must meet the relevant tax rules, and private use may need to be excluded.
Does MTD replace my annual tax return?
MTD changes digital record keeping and reporting obligations for those within scope. The annual Self Assessment process and final tax position still need to be completed in line with HMRC's current rules.
Can SV&Co deal with HMRC for me?
Once the correct agent authority is in place, we can deal with relevant HMRC correspondence and submissions on your behalf.
Reviewed by
Sandip Vadher, PhD FCCA
Founder of SV&Co Accountancy. Fellow Chartered Certified Accountant with more than 20 years of finance and accountancy experience.
Need help with your return?
Tell us what you need help with.
WhatsApp is the preferred fast-response route. You can also use the short form to show us the type of Self Assessment help you need.
Official sources used for this draft: Self Assessment deadlines, HMRC tax return checker, self-employed expenses, payments on account, MTD for Income Tax, self-employed National Insurance rates.