Best Self Assessment Software 2026: File Your Tax Return Online

Filing a Self Assessment tax return is something millions of UK taxpayers do every year, yet the process remains confusing for most. HMRC's own online filing system works but offers no guidance, no error checking, and no help with the calculations that determine how much you owe. Third-party software fills this gap, but the options range from simple filing tools to comprehensive bookkeeping platforms that include SA filing as one feature among many.

The right choice depends on your situation. If you keep meticulous records already and just need a way to file, a dedicated filing tool might be all you need. If your record-keeping is inconsistent and you want something that tracks your finances throughout the year, a bookkeeping platform that includes SA filing will serve you better — especially with MTD quarterly submissions now a requirement for many.

The Two Types of SA Software

It is important to understand the distinction:

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Filing-only tools guide you through your tax return, help with calculations, and submit to HMRC. You provide the numbers. They handle the forms and filing.

Year-round bookkeeping platforms track your income and expenses throughout the year and use that data to populate your tax return automatically. The filing is the end point, not the starting point.

With Making Tax Digital requiring quarterly submissions for many taxpayers, the filing-only approach is becoming less viable as a standalone solution. You need to maintain digital records and submit quarterly updates anyway, so having software that does both makes increasing sense.

Accounted

From £14/month (Professional plan and above for SA filing)

Accounted is firmly in the year-round bookkeeping category. Throughout the year, the AI bookkeeper Penny categorises your transactions, scans your receipts via WhatsApp, and maintains your records. When it is time to file your Self Assessment, the return is populated automatically from your existing records.

Accounted supports 11 of the 13 SA schedules, which covers the vast majority of taxpayers including those with self-employment income, property income, capital gains, pension income, and foreign income. The AI pre-checks your return for common errors before submission, and seasonal tax nudges remind you of deadlines and opportunities (like pension contributions before year end).

The MTD compliance means your quarterly updates and end-of-period statement flow naturally into your annual Self Assessment return. You are not maintaining two separate processes.

Annual cost: £288/year (Professional plan at £24/month) What you get: Year-round bookkeeping, AI categorisation, WhatsApp receipt scanning, MTD quarterly submissions, SA filing with 11 schedules, bank feeds, accountant portal access.

GoSimpleTax

From £58.50/year

GoSimpleTax is the best pure filing tool available. The guided process walks you through each section of the Self Assessment return in plain English, explaining what goes where and why. Real-time tax calculations update as you enter figures, so you can see exactly how each entry affects your bill.

The interface is clear and the pricing is transparent. You pay per tax year, and the price covers everything — all schedules, unlimited amendments, and filing to HMRC. For someone who keeps their own records in a spreadsheet and just needs reliable filing software, GoSimpleTax is hard to fault.

The limitation is equally clear: GoSimpleTax is not a bookkeeping platform. There are no bank feeds, no receipt scanning, no transaction categorisation. You need to know your numbers before you start. With MTD now requiring quarterly digital submissions, you would need a separate tool for that.

Annual cost: From £58.50/year What you get: Guided SA filing, real-time calculations, all schedules, HMRC submission, unlimited amendments.

TaxCalc

From around £30/year for individual filers

TaxCalc is a well-established SA filing tool used by both individual taxpayers and accountancy practices. The individual version provides guided SA filing with comprehensive schedule support. Tax calculations are accurate and the software handles complex tax situations — including multiple income sources, capital gains, and foreign income — competently.

TaxCalc also offers a practice version with multi-client management, making it popular with accountants who handle many returns. The desktop version has a loyal following, though the cloud version has improved significantly.

Annual cost: From around £30/year (individual) What you get: Comprehensive SA filing, strong calculation engine, all schedules, desktop and cloud options.

FreeAgent

From £14.50/month (free with NatWest)

FreeAgent combines year-round bookkeeping with Self Assessment filing. The SA filing process pulls data from your FreeAgent records and guides you through additional entries that are not captured through bookkeeping (such as pension income or bank interest).

The tax timeline feature is excellent for Self Assessment preparation. Throughout the year, it shows estimated tax bills and upcoming deadlines. By the time you reach the filing date, your estimated bill is rarely a surprise.

For NatWest, Royal Bank of Scotland, and Ulster Bank customers, FreeAgent is free, making it arguably the best value SA filing option — if you are willing to use it for bookkeeping throughout the year.

Annual cost: £174/year (or free with NatWest) What you get: Year-round bookkeeping, bank feeds, expense tracking, SA filing, tax timeline, MTD submissions.

ANNA

Business account with integrated tools

ANNA combines a business bank account with basic bookkeeping and tax filing capabilities. Because your banking and accounting are in the same system, transactions are automatically captured and categorised. Self Assessment filing is available for simple tax situations.

The strength is convenience — one app handles banking, bookkeeping, and filing. The weakness is depth. If your tax situation is more than straightforward self-employment income, ANNA's filing capabilities may not cover all the schedules you need.

Annual cost: Varies by account plan What you get: Combined banking and bookkeeping, automatic transaction capture, basic SA filing.

Xero (with Xero Tax)

From £15/month + accountant filing via Xero Tax

Xero itself does not file Self Assessment returns directly. Instead, your accountant uses Xero Tax — a separate product within the Xero ecosystem — to prepare and file your return using data from your Xero books.

This means you cannot self-file through Xero. You need an accountant on Xero to handle the SA filing. For many people this is fine — they use an accountant anyway. But if you want to file your own return, Xero is not a standalone solution.

Annual cost: £180/year minimum (Xero Standard at £15/month) plus accountant fees What you get: Year-round bookkeeping with bank feeds, robust categorisation tools, SA filing through your accountant.

Price Per Year Comparison

| Software | Annual Cost | Bookkeeping | SA Filing | MTD Quarterly | Self-File | |---|---|---|---|---|---| | GoSimpleTax | From £58.50 | No | Yes | No | Yes | | TaxCalc | From £30 | No | Yes | No | Yes | | Accounted | From £288 | Yes (AI) | Yes | Yes | Yes | | FreeAgent | From £174 (or free) | Yes | Yes | Yes | Yes | | ANNA | Varies | Yes (basic) | Yes (basic) | Developing | Yes | | Xero + Tax | From £180 + fees | Yes | Via accountant | Yes | No |

Which Approach Is Right for You?

Choose a filing-only tool if:

• You keep accurate records already (in a spreadsheet or elsewhere)
• You do not need MTD quarterly submissions (income below the threshold)
• You want the cheapest option for annual filing
• Your tax situation is straightforward

Choose a year-round platform if:

• You need MTD quarterly submissions
• Your record-keeping needs improvement
• You want your SA return populated automatically from your records
• You want receipt scanning and bank feeds throughout the year

Choose an accountant-filed solution if:

• Your tax affairs are complex
• You prefer professional review before submission
• You already work with an accountant

Our Recommendation

GoSimpleTax is the best filing-only tool for the price. No question. If you genuinely just need to file and your records are already in order, it does the job well and affordably.

For everyone else — particularly those now facing MTD quarterly submissions — a year-round platform that includes SA filing provides far more value. Accounted's AI handles the bookkeeping throughout the year, so when filing time arrives, your return is essentially ready. The seasonal tax nudges help you plan ahead, and the confidence scoring ensures your records are reliable before they flow into your return.

Try Accounted Free

Start a free trial at accounted.io and let Penny organise your finances throughout the year. When January arrives, your Self Assessment return will be populated from twelve months of accurate, AI-categorised records rather than assembled from a panic-driven search for missing receipts. No card required.

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