Self Assessment accountant fees typically fall between £150 and £500 plus VAT. A straightforward return with one or two income sources sits at the lower end, while more complex returns – involving things like property, capital gains, cryptocurrency or foreign income – push towards the higher end and beyond.
In this blog we’ll take a look at the average costs depending on your circumstances, giving you a complete breakdown of what affects the price as well as some frequently asked questions.
What’s the average cost of a Self Assessment accountant?
That £150-£500 range covers a lot of ground, and where you land mostly comes down to how much work your accountant needs to do behind the scenes. This can vary based on how many transactions there are to check, how many income sources need entering, and how much back-and-forth it takes to get everything prepared before it’s submitted.
Here’s a rough breakdown of what you might expect to pay based on your situation:
| Situation | Typical fee range | Why |
| Simple return, with one or two income sources | £150-£250 | Less data to process, straightforward calculations |
| Self-employed with a few clients, basic expenses | £200-£350 | More transactions to categorise and check |
| Property income, capital gains, high volume crypto/stock trades, or foreign income | £350-£500+ | More complex calculations and cost-basis tracking |
Does Self Assessment cost more if you’re a sole trader or a limited company director?
It depends on what you’re actually paying for, and how your accountant structures their fees.
If you’re a sole trader, your Self Assessment fee is usually your whole tax filing cost – there’s no separate company return sitting alongside it, so the £150-£500 range above is a fair reflection of what you’ll pay in total.
Self Assessment tax returns for company directors are a bit different. Your personal Self Assessment (which will refer to things like salary and dividends) is separate from your company’s accounts and Company Tax Return (CT600). Some accountants quote Self Assessment as a standalone fee on top of your company work; others bundle it into an overall package (even if you don’t actually need it). Either way, it’s worth asking your accountant to break the quote down so you know exactly what’s covered.
What affects how much you’ll pay?
It really comes down to the complexity of your income and again, how your accountant structures their fees! The main factors are:
- How much you earn and/or how many sources of income you have: Employment, dividends, pensions and so on all mean more data for your accountant to work through
- Property income: Rental properties bring extra complexity, like tracking individual expenses and mortgage interest relief
- Capital Gains Tax: Selling shares, property or crypto means more complex calculations and cost-basis tracking
- Foreign income: Double-taxation treaties and cross-border rules mean more work for your accountant
- The state of your records: Messy bookkeeping takes longer to untangle, which usually means a higher rate. Using bookkeeping software throughout the year can help you avoid this altogether.
Where you’re based matters too. A local accountant in London may charge more than an online accountant based elsewhere in the UK, simply because of the difference in their overheads.
All of that said, these factors tend to have more of an impact if your accountant uses a variable or hourly rate rather than a fixed fee.
Fixed fee vs hourly rate: what’s the difference?
A fixed fee means you know exactly what you’ll pay before any work begins, with no surprise costs further down the line. Personal tax returns tend to follow a fairly predictable process, so accountants can price them accurately from the outset based on how much you tend to earn. Because the fee doesn’t change based on how long the job takes, there’s a built-in incentive to work efficiently rather than dragging things out.
That said, hourly rates do still crop up in a few situations, for example if you:
- Have chaotic paperwork and receipts: This is time-consuming to organise but must be done before any tax work can start
- Are under HMRC investigation: How long this’ll take is unpredictable
- Need specialised advice: E.g. inheritance tax planning or corporate restructuring – every case is different
DIY vs hiring an accountant for Self Assessment: is it worth the cost?
Going the DIY route can look cheaper on paper, but it’s worth weighing up the true cost before deciding. Online accounting software such as Pandle or Xero will help you organise your records and prepare your tax return, categorise everything correctly, and reconcile your accounts. If your tax affairs are more complicated or you have multiple sources of income to collate, then this process might end up being time-consuming, and eat up several hours every month.
There’s also the risk factor: missing out on tax deductions or allowances could end up costing you far more than an accountant’s fee ever would.
| Filing it yourself | Hiring an accountant | |
| Upfront cost | £0 | £150-£500+ |
| Time required | Several hours a month | Minimal, once records are handed over |
| Risk of missed deductions | Higher | Lower |
| HMRC compliance support | None | Included |
| Peace of mind | Depends on confidence with tax rules | Higher |
Hiring a professional frees up your time and gives you peace of mind that you’re staying compliant – especially if your return isn’t straightforward. Accountants also keep on top of changing tax laws, know how to spot legitimate expenses you might miss, and can offer strategic advice beyond basic bookkeeping, from cash flow forecasting to tax planning.
It really depends on your situation. If your accounts are simple, DIY filing (with the help of software) could work well. If they’re not, it’s worth bringing in an accountant.
Self Assessment fees FAQs
How much does an accountant charge for a simple Self Assessment?
A simple return, such as one extra income source alongside employment, tends to sit at the lower end of the £150-£500 range.
Is it cheaper to use an online accountant?
Often, yes. Online accountants tend to have lower overheads than local, city-based firms, which can be reflected in their fees.
Can I claim accountant fees as a tax deduction?
If the fee relates to your self-employment or rental income, you can usually claim it as an allowable business expense. The portion relating to purely personal income isn’t deductible.
Does filing late cost more?
Some accountants charge more for last-minute filing close to the deadline. For example, if you’re filing online then the closer you get to the January deadline, the harder it’ll be to squeeze your return in around everyone else’s. On top of that, HMRC charges its own late filing penalties, so it pays to get your records over early.
Self Assessment can be tricky! Learn more about our online accountancy services and call 020 3355 4047, or get an instant online quote.
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