Best Tax Software for UK Self Assessment in 2026 (and How to Pick the Right One for You)
Making Tax Digital arrived in April 2026, and the software you pick for your Self Assessment matters more than ever. Here's how the main options compare, and which one actually fits your situation.
Quick overview
| Fact Type | Key Information |
|---|---|
| MTD start date | Mandatory from 6 April 2026 for sole traders and landlords with qualifying income above £50,000 |
| Future thresholds | Above £30,000 from April 2027 and above £20,000 from April 2028 |
| Quarterly updates | Four per year, due 7 August, 7 November, 7 February and 7 May |
| Final Declaration | Due by 31 January following the end of the tax year |
| HMRC’s free online service | Does not support MTD ITSA |
| First-year penalty relief | No penalty points for late quarterly updates in 2026/27. The Final Declaration deadline of 31 January 2028 is not covered |
For most people with anything beyond a very simple return, Taxd is the strongest Self Assessment software choice in 2026: it's HMRC-recognised, covers the full SA100 and every supplementary page, supports Making Tax Digital quarterly updates, and starts from £99. If your return is genuinely basic and MTD doesn't apply to you, HMRC's free online service is still fine.
Choosing tax software should be simple. But search "best self assessment software" and you'll find a wall of generic lists that don't actually help you decide.
So let's make this useful. Whether you're a freelancer filing for the first time, a landlord juggling property income, or someone who's just realised Making Tax Digital applies to you this year, this guide breaks down the best options for 2026 and tells you exactly which one fits your situation.
Quick Comparison: Best UK Self Assessment Software 2026
Not sure where to start? Here's the short version. Each option below is covered in more detail further down.
| Software | Annual Cost | MTD ITSA Ready | Best For |
|---|---|---|---|
| Taxd | From £99 | Yes | Complex returns: expats, landlords, multiple income sources |
| HMRC Online Service | Free | No | Very simple returns only |
| TaxCalc Individual | From ~£38 | Yes | In-depth, complex self-employed returns |
| Untied | ~£100/yr | Yes | Self-employed who want mobile income tracking |
| QuickBooks Sole Trader | ~£120/yr (£10/mo) | Yes | Existing QuickBooks users |
Important note on HMRC's free service: It does not support MTD ITSA. If your income exceeds £50,000 and you're a sole trader or landlord, you can no longer rely on it as your primary filing tool.
The Best UK Self Assessment Software Options in 2026
1. Taxd - Best for Complex Returns and Specialist Situations
If your tax situation is anything other than basic, Taxd is worth a serious look. It's built specifically for the people the big accounting platforms tend to overlook: expats, non-resident landlords, people with multiple income sources, and those navigating supplementary pages like SA105 (property income) or SA109 (residence and remittance).
Cost: Personal tax returns from £99. MTD ITSA quarterly updates and digital record-keeping are also supported.
What makes it different:
- Covers the full SA100 form and all supplementary pages (SA101 to SA110).
- Step-by-step guidance that explains what each question actually means.
- HMRC-recognised and supervised by the Association of Taxation Technicians.
- Supports MTD ITSA with quarterly updates and digital record-keeping.
- Flat-fee pricing, so you know what you're paying upfront.
- Human tax specialists available on live chat as you complete your return.
It's the kind of tool that works whether you're a PAYE employee with some rental income on the side, a freelancer with overseas clients, or an expat trying to work out your UK tax position from abroad.
Start your Self Assessment with Taxd
2. HMRC Online Service - Free, But Limited
The HMRC online service is still an option for the simplest of returns: think a single employment income source with a small amount of savings interest. It's free, it's official, and it works.
The catch: It does not support Making Tax Digital for Income Tax. If you earn over £50,000 from self-employment or property, you're now required to use MTD-compatible software. The HMRC service won't cut it for quarterly updates.
Best for: Employees with a very simple additional income source who are not caught by MTD ITSA.
3. TaxCalc Individual - Best for Depth and Complexity
TaxCalc is a well-established name in UK tax software, with individual plans starting from around £38 per year. It's form-based, thorough, and well-suited to people who want granular control over their return.
Cost: From around £38/year.
Best for: Self-employed individuals with complex deductions, capital gains, or multiple income streams who are comfortable working through a detailed form.
Worth knowing: TaxCalc is MTD ITSA compatible, so it handles quarterly updates if you're in scope.
4. Untied - Best for Mobile-First Self-Employed
Untied is built around income tracking throughout the year, not just at filing time. You connect your bank, categorise transactions as you go, and by the time your return is due, most of the work is already done.
Cost: Around £100/year.
Best for: Sole traders and gig economy workers who want to track income and expenses on their phone rather than scrambling at year-end.
MTD status: Fully compatible, which makes it a solid choice for those who want to stay on top of quarterly updates without a separate bookkeeping tool.
5. QuickBooks Sole Trader - Best If You're Already in the QuickBooks Ecosystem
QuickBooks retired its old Self-Employed product and replaced it with QuickBooks Sole Trader, priced at around £10 per month. If you're already using QuickBooks for invoicing or bookkeeping, it keeps your record-keeping and MTD submissions in one place.
Cost: Around £120/year (£10/month).
Best for: Freelancers and sole traders already committed to the QuickBooks platform who want bookkeeping and MTD filing together.
MTD status: Supported, covering both quarterly updates and the Final Declaration.
What Making Tax Digital Means for Your Software Choice in 2026
This is the big change for 2026, and it's worth understanding before you pick a tool.
Making Tax Digital for Income Tax Self Assessment (MTD ITSA) went live on 6 April 2026. It's a phased rollout, and here's where things stand:
| Income threshold | Mandatory from |
|---|---|
| Over £50,000 (sole traders and landlords) | 6 April 2026 |
| Over £30,000 | 6 April 2027 |
| Over £20,000 | 6 April 2028 |
What changes under MTD ITSA?
Instead of one annual tax return, you now submit four quarterly updates throughout the year, followed by a Final Declaration. The quarterly deadlines are:
- Q1: 7 August
- Q2: 7 November
- Q3: 7 February
- Q4: 7 May
The Final Declaration (which replaces the traditional self assessment return) is still due by 31 January following the end of the tax year.
The soft-landing period
HMRC has confirmed a soft landing for the 2026/27 tax year. This means no penalty points will be issued for late quarterly updates during this first year. The Final Declaration deadline of 31 January 2028, however, is not covered by the soft landing.
The practical takeaway: If MTD applies to you, your software must be able to submit quarterly updates directly to HMRC. The free HMRC online service cannot do this. You need MTD-compatible software, and you need it now.
How to Choose the Right Self Assessment Software for You
The right tool depends entirely on your situation. Here's a simple way to think about it, and if you want a deeper walkthrough of the decision, our guide on how to choose the best Self Assessment tax return software goes into more detail.
Your tax situation is straightforward (PAYE with minor extras)
If you're employed and just have a small amount of savings interest, a one-off freelance project, or Gift Aid to declare, the HMRC online service is still fine, as long as your income doesn't put you in scope for MTD.
You're self-employed or a landlord with income over £50,000
MTD ITSA applies to you now. You need software that handles quarterly updates and keeps digital records. Taxd, TaxCalc, Untied, and QuickBooks all qualify. The choice comes down to how hands-on you want to be with your bookkeeping.
You have a complex tax situation
This is where most generic tools fall short. If you're an expat, a non-resident landlord, someone with overseas income, or a director with both salary and dividends, you need software that covers the full range of supplementary pages without forcing you to call an accountant for every edge case. Taxd is built for exactly this, and it helps you claim every allowable expense you're entitled to along the way.
You want to track income throughout the year (not just at filing time)
If you'd rather categorise transactions as they happen than scramble through bank statements in January, look at Untied. The mobile-first approach suits sole traders and gig workers who want their tax situation visible all year round.
A quick rule of thumb:
- Simple return, no MTD: HMRC online service (free).
- MTD in scope, standard self-employment: TaxCalc or Untied.
- Complex situation (expat, landlord, multiple sources): Taxd.
- Already using QuickBooks: Stay in the QuickBooks ecosystem.
Frequently Asked Questions
What is the best free tax software for UK Self Assessment?
The HMRC online service is the only genuinely free option for UK Self Assessment. It works well for very simple returns but does not support Making Tax Digital for Income Tax. If MTD applies to you (income over £50,000 from self-employment or property), you'll need a paid MTD-compatible tool.
Do I need to use MTD software in 2026?
Only if your qualifying income from self-employment or property exceeded £50,000 in the 2024/25 tax year. If so, MTD ITSA became mandatory for you on 6 April 2026. The threshold drops to £30,000 from April 2027 and £20,000 from April 2028.
Can I still use HMRC's online service to file my Self Assessment?
Yes, for a standard annual return if you're not caught by MTD ITSA. But if you're in scope for MTD, you must use HMRC-recognised software that supports quarterly digital submissions. The free HMRC service does not support this.
What does MTD ITSA mean in practice?
Instead of one annual tax return, you submit four quarterly updates to HMRC (by 7 August, 7 November, 7 February, and 7 May), followed by a Final Declaration by 31 January. Your software handles the submissions directly. See HMRC's Making Tax Digital for Income Tax guidance on GOV.UK for full details.
Is Taxd HMRC-recognised?
Yes. Taxd is HMRC-recognised software for Self Assessment and is supervised by the Association of Taxation Technicians. It supports the full SA100 form, all supplementary pages, and MTD ITSA quarterly updates.
The Bottom Line
The market for UK self assessment software has never been bigger, but most of it is built for the simplest possible case. If your situation is even slightly complicated, that's where a lot of tools start to struggle.
For 2026 specifically, the MTD ITSA rollout means the stakes are higher than they used to be. Picking the wrong tool now could mean scrambling to switch mid-year when quarterly deadlines start stacking up.
Our recommendation: If you have any complexity in your tax situation, start with Taxd. It's built for exactly the situations that trip people up, it's HMRC-recognised, and at £99 it still costs less than most accountants charge for a single return.
If you're genuinely just filing a simple return with no MTD obligation, the HMRC free service is still perfectly adequate. But most people reading this guide are in a more nuanced position than that.
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