A sole trader accountant turns a year of records into a return that stands up, files it as your registered HMRC agent, and tells you what to pay and when. The fee is driven by the state of your records rather than by what you earned, and any firm worth using will quote it as a fixed figure before any work starts.
This page answers the question most sole traders actually have, which is not what an accountant does. It is whether the money is worth it, and what makes one quote twice another.
We have not put a price list on this page, and that is deliberate. A number with no scope attached is a number you cannot rely on, and the firms that publish one usually attach conditions underneath it that move it anyway. What follows is the honest version: what the work is, what moves the cost, and when you should not pay for it at all.
What does an accountant for sole traders actually do?
- Agent authorisation with HMRC, so your accountant can see what HMRC already holds on you.
- Records pulled together and categorised, which on most returns is the bulk of the job.
- Allowable and non allowable expenses separated, with the reasoning shown rather than assumed.
- Income Tax and Class 4 National Insurance computed, with the payments on account worked out at the same time.
- The return reviewed with you, then filed once you sign it off.
- HMRC correspondence afterwards, going to the agent rather than to you.
Fifteen minutes is enough to scope a sole trader return and put a fixed number on it. If the answer is that you do not need an accountant, we will say that instead.
Or call 029 2002 6505
What determines how much a sole trader accountant costs?
Six things, and only two of them have much to do with how much you earned.
What decides the fee on a sole trader tax return
Six things. Only two of them have much to do with how much you earned.
A categorised bank feed or a carrier bag. The single biggest factor in the price.
One trade is one schedule. Trade plus rent plus dividends is three, and they have to agree with each other.
Forty invoices a year is not four hundred card payments a month.
Either one adds returns and deadlines that have nothing to do with January.
A late registration or an amended year is separate work, not an add on to this year.
Not a surcharge, a capacity limit. Late January is when firms stop taking new work on.
The counterintuitive one. Earnings barely feature. A quiet year with chaotic records costs more to file than a busy year with clean ones.
The one that surprises people is the first. A quiet year with a shoebox costs more to file than a busy year with a categorised bank feed, because the fee is mostly time spent working out what each line is, not time spent typing figures into a form.
What are the options for filing a sole trader tax return?
There are three routes and all of them are legitimate. The comparison that matters is not price against price, it is cash against time against who answers HMRC when something comes back.
Three ways to get a sole trader tax return filed
All three are legitimate. They differ in what you spend and what risk you keep.
Cheapest in cash, costs a weekend or three, usually in January. You carry every judgement about what is allowable, and the penalty if one is wrong.
Records get done properly through the year, filing is still on you. You carry the tax treatment, the payments on account and the HMRC correspondence.
One fixed fee agreed before the work starts, filed as your HMRC agent. You give us the records and sign it off. The rest sits with the agent.
The honest comparison. It is not price against price. It is cash against time against who answers HMRC when something comes back.
“I scheduled a phonecall appointment and missed it… Great start. Buhir then called in his own time on a Saturday evening to outline the services he offers. Despite me deciding against using his services he gave me a step by step guide to complete my Self Assessment and sent me tons of helpful info.”
Most sole traders do not need more accountancy. They need the right amount of it, priced before it starts.
Which expenses do sole traders get wrong most often?
Almost none of the money lost on a sole trader return is lost at the filing stage. It is lost in the expense decisions made months earlier, and the same handful come up every season.
Working from home. There is a flat rate based on hours worked from home each month, and there is the proportion method, where you apportion the actual household costs by rooms and time used. The flat rate is simpler and almost always smaller. People use it because it is easier to defend, then never check whether the other method would have been worth the arithmetic.
Mileage. Either the approved mileage rates per business mile, or actual running costs with a private use adjustment and capital allowances on the vehicle. Once you have chosen for a vehicle you stay with it, so the choice in year one matters for years after. The mileage log is the bit that gets abandoned in March.
Clothing. Protective gear and genuine uniform are allowable. Ordinary clothes you happen to wear for work are not, however strict the dress code, because they also serve as everyday clothing. This is the single most commonly disallowed line we see.
Training. Keeping an existing skill current is allowable. Acquiring a new skill that lets you do something you could not do before is capital in nature and is not. The line is genuinely fine and worth asking about before you book the course, not after.
Pre trading costs. Expenses in the seven years before trading started, that would have been allowable had the trade been running, are treated as incurred on day one. Most people filing a first return never claim them because nobody told them it was possible.
The split that is not an expense at all. Buying a van, a laptop or equipment is capital, and relief comes through capital allowances rather than as a line in the expenses. Put it in the wrong place and the profit is wrong, even though the cash left the account either way.
The shoebox is not the problem. Twelve months of decisions nobody recorded at the time is the problem.
Does a sole trader accountant work differently by trade?
Sole trader is a legal status, not a type of business, and the work changes a great deal depending on what you do.
Building and the trades. Usually CIS deductions to reconcile, materials against labour, a van, tools and often subcontractors of your own. The return is frequently a refund rather than a bill, because tax has already been taken at source, and that refund is the reason filing early is worth money.
Hair, beauty and therapy. Chair or room rental, stock, equipment on capital allowances, and the question of whether someone working in your space is self employed or actually employed by you. That last one is the expensive one to get wrong.
Retail, florists and market traders. Takings records that stand up, stock at the year end, card terminal fees, and in some cases a VAT threshold creeping closer without anyone watching it.
Drivers and couriers. The mileage or actual costs choice, platform income reported directly to HMRC by the platform, and the fact that gross platform earnings are not the figure that goes on the return.
Consultants and creatives. Usually the simplest accounts and the most complicated tax position, because there is often employment income alongside, pension headroom worth using, and a real question about whether a limited company now fits better.
Chair rental, stock and capital allowances. The accounts are small, the decisions are not.
What does HMRC charge for filing a sole trader return late?
The fee is only half the comparison. The other half is what HMRC charges when a return is late or an income source was never declared, and those numbers are published.
Filing late is £100 the moment 31 January passes, with no tax due and no excuse needed. From three months it is £10 a day, capped at £900. At six months it is 5 per cent of the tax or £300, whichever is greater, and the same again at twelve. A late return with no tax to pay still reaches £1,600.
Paying late is charged separately at 5 per cent after 30 days, again at six months and again at twelve, with late payment interest running at 7.75 per cent as at 10 October 2026. And never registering at all is a different regime again, with failure to notify penalties that reach 100 per cent of the tax where the behaviour was deliberate and concealed.
When does Making Tax Digital apply to a sole trader?
Worth knowing now, because it changes what good bookkeeping has to look like.
- Already live. Qualifying income over £50,000 in 2024 to 2025 brought you in from 6 April 2026, with the first quarterly deadline on 7 August 2026.
- From 6 April 2027. Qualifying income over £30,000 in 2025 to 2026.
- From 6 April 2028. Qualifying income over £20,000 in 2026 to 2027.
- None of it changes the 2025 to 2026 return or the 31 January 2027 deadline.
If you are close to a threshold, the useful question is not what Making Tax Digital costs. It is whether your records would survive quarterly reporting in their current state. Our page on how the income threshold is worked out covers which figure HMRC actually tests.
“Buhir was incredibly helpful. This was my first time working with an accountant after several years of doing my self assessment taxes myself and I highly recommend his services. He also gave me plenty of advice on how to organise my finances moving forward.”
Want the figure before you commit?
Tell us what your year looked like on a free fifteen minute call and we will quote a fixed fee, or tell you honestly that you do not need us.
What happens on the first call with an accountant?
Fifteen minutes, no paperwork needed, nothing signed at the end of it.
We ask what the trade is, roughly what it turned over, how the records are kept, whether there is other income alongside, and whether anything unusual happened in the year. That is enough to tell you three things: what your return involves, what the fixed fee is, and what we need from you to start.
If the honest answer is that your accounts are simple enough to file yourself, you will get that answer instead of a quote. We would rather lose a small fee than take money for work you did not need, and a fair number of the people we turn away come back two years later when the business has grown.
Get the scope and the fixed fee in one call, before you commit to anything. If you do not need us this year we will tell you.
Or call 029 2002 6505
Should a sole trader become a limited company?
This is the question that follows the fee question, and the honest answer is that it turns on three things rather than on a profit figure somebody quoted you in a pub.
How much you take out. A company pays corporation tax at 19 per cent on profits under £50,000 and 25 per cent above £250,000, with marginal relief between. But getting money out costs again, through dividend tax at 10.75 and 35.75 per cent from 6 April 2026, or through salary and employer National Insurance at 15 per cent above the £96 a week secondary threshold. Profit you leave in the company is taxed once. Profit you take out is taxed twice.
What the administration is worth to you. A company means annual accounts at Companies House nine months after the year end, a corporation tax return twelve months after, corporation tax paid nine months and a day after, a confirmation statement, and director and person with significant control identity verification, which became a legal requirement on 18 November 2025. That is real work and it has a real cost.
Whether Employment Allowance is available. For a one director company where that director is the only employee over the secondary threshold, it is not, which quietly weakens the classic small salary and dividends plan.
None of that is a reason not to incorporate. It is a reason to model it properly on your own numbers before you do, which takes about twenty minutes and is part of the free call.
Whether a limited company fits is an arithmetic question about what you take out, not a status upgrade.
We work with sole traders across Cardiff, Newport and Bristol, and remotely across the rest of England and Wales.
Sole trader accountants: common questions
What does an accountant for a sole trader actually cost?
There is no single number, and anyone quoting one without asking about your records is guessing. The fee is driven by the state of the bookkeeping, how many income sources are on the return, transaction volume, whether VAT or payroll is involved, and whether earlier years need correcting. We quote a fixed figure on the free call once we know those, and it does not move unless the scope does.
Is it worth paying an accountant if I only earn a little?
Sometimes not, and we will say so. If you have one trade, a handful of invoices, no VAT and clean records, the return is a job you can do yourself. It becomes worth paying for when there is more than one income source, when the expense judgements are not obvious, or when the time it takes you is worth more than the fee.
Do I have to file at all?
If your gross trading income was over £1,000 in the tax year, before expenses, yes. That threshold is on gross income, not profit, so a loss making year can still need a return. The government has said it intends to raise the figure to £3,000 within this Parliament, but no date has been set, so £1,000 is what applies now.
What happens if I registered late?
The registration deadline for the 2025 to 2026 tax year was 5 October 2026. If you missed it, register now. HMRC will set your filing deadline at three months from the date on its letter rather than 31 January, and the exposure is a failure to notify penalty rather than a late filing one.
Can I claim the accountancy fee against my tax?
The fee for preparing the business accounts and the trade pages is normally an allowable business expense. The part that relates purely to your personal tax affairs is not. Where a single fee covers both, it has to be apportioned, and we show you how it has been split.
Should I be a limited company instead?
It depends on profit level, what you take out, and whether you want the administration. Incorporating adds accounts, a confirmation statement, director identity verification and a second layer of tax on getting money out. It is worth modelling rather than assuming, and we will do that on the call rather than selling you the answer.
Can I claim for working from home as a sole trader?
Yes, either at the flat rate based on hours worked from home each month, or by apportioning the actual household costs by rooms and time used. The flat rate is simpler and usually smaller. Which one is better depends on your actual bills, so it is worth running both once rather than defaulting.
Can I claim my clothes?
Protective equipment and genuine uniform, yes. Ordinary clothing you wear for work, no, because it also serves as everyday clothing. This is the most commonly disallowed expense we see on sole trader returns.
Can I claim a course or training?
Keeping an existing skill current is allowable. Learning something new that lets you do work you could not previously do is capital in nature and is not. Ask before you book rather than after.
I bought a van. Is that an expense?
Not as a straight expense. A van, a laptop or equipment is capital, and relief comes through capital allowances rather than through the expenses figure. Putting it in the wrong place makes the profit wrong even though the money left the account either way.
Should I become a limited company?
It depends on how much profit you take out rather than how much you make. Profit left in a company is taxed once at 19 or 25 per cent. Profit taken out is taxed again, at 10.75 or 35.75 per cent on dividends from 6 April 2026. Add the accounts, the confirmation statement and director identity verification and it has a real administrative cost. Worth modelling on your own figures before deciding.
I am a subcontractor under CIS. Do you handle that?
Yes. CIS deductions are tax already paid, so a CIS return is often a refund rather than a bill. That is the main argument for filing in October rather than January, because the refund arrives sooner.
Related reading
Tell us what your year looked like and we will put a fixed number on it, or tell you that you are better off filing it yourself. Both answers are free.
Thresholds, penalties, deadlines and interest stated as published on GOV.UK at 10 October 2026. General information, not advice on your own position.
