How much does a self assessment tax return cost

A self assessment return can be a few figures or a long set of pages, and fees follow the complexity. Most price guides split returns into rough tiers. A simple return, for someone with employment income and perhaps a small extra source, sits at the bottom. Self-employment adds the work of checking income and expenses. Income from a rental property, capital gains on shares or property, cryptocurrency disposals and foreign income each add supplementary pages and calculations. Sleek, updated 26 October 2026, says that cryptocurrency disposals, foreign income, or multiple rentals can push the fee past £400.

Timing matters too. Work that arrives in the last few weeks before the 31 January online deadline competes with every other late return, and some firms charge more for it. Records that are incomplete or need sorting will usually add to the bill.

These ranges come from two price guides published by firms that sell self assessment services, and from a survey of accountants. They show what the sources say is typical, not what any particular firm will charge. The IRIS survey was carried out in February and March 2024, so it is older than the other two. None of these figures is a Sussex price.

Several online services publish a single fixed price for a standard return. Listed alphabetically, and not as a recommendation:

• Crunch lists a standard self assessment at £240, shown as £168 +VAT with a 30% discount code, which is a promotional price.
• GoForma lists a one-off self assessment tax return at £198 (VAT not stated).
• Sleek lists its own fixed fee at £275 + VAT.
• Taxfix, formerly TaxScouts, shows prices from £99, but its page is inconsistent, giving plan cards of £169, £249 and £499 alongside a table of £99, £149 and £349 for the same three plans. VAT is not mentioned, and capital gains are charged at a higher fee with no amount given.

The dates on these pages are not shown; we checked them on 5 November 2026.

Marketplaces quote lower figures. Airtasker, updated 26 June 2026, gives a median of £150 per task and £120 to £250 for a sole trader return, but its basic individual return is given as £90 to £140 in one place and £90 to £180 in another on the same page, and it bases its figures on its own job data without giving a sample size. Bark's figures, labelled 2025, give £95 to £250 for a one-off self assessment, and Unbiased, updated 23 July 2026, gives £150 to £600. None of these states VAT.

Sleek also gives regional figures for a single return, with Central London at £250 to £450 and the rest of England at £150 to £400, excluding VAT, and Airtasker gives ranges for a handful of cities. Neither gives a Sussex or South East figure.

A one-off fee normally covers preparing the return from the information you provide, calculating the tax and filing it with HMRC once you have approved it. You will need to authorise the accountant as your agent. Things that are often charged separately are:

• registering you for self assessment if this is your first return, which must be done by 5 October after the end of the tax year
• supplementary pages for property, capital gains or foreign income, where the base price covers only a simple return
• sorting out incomplete records
• dealing with HMRC questions after the return is filed
• tax advice beyond the return itself, which some firms bill by the hour

Ask whether payments on account are explained in the quote. If last year's bill was £1,000 or more, HMRC may ask for advance payments by 31 January and 31 July, each half of the tax you owed last year, which can come as a surprise.

• Gather your P60, bank interest, rental figures and any disposal details before you ask for a quote, so the accountant can price the actual job.
• Ask for the quote early in the season rather than in January.
• If your return is simple, you might file it yourself through HMRC's online service and pay only for a one-off check or question. Crunch, for example, lists an "Ask an accountant" service at £26+VAT.
• Avoid penalties, which can cost more than the fee. A late return brings an initial £100 penalty, and after 3 months daily penalties of £10 per day, up to a maximum of £900.

• Is this a fixed fee, and does it cover every page my return needs?
• Is there an extra charge for rental income, capital gains, crypto or foreign income?
• Does the price include VAT?
• Will you register me with HMRC if needed, and is that included?
• What happens if HMRC asks questions after the return is filed?
• When do you need my paperwork to meet the 31 January deadline?

Our page on self assessment tax returns explains the process, and our self assessment deadlines guide sets out the key dates.