If you're a self-employed associate dentist, the way you report your income to HMRC is about to change. From 6 April 2026, Making Tax Digital for Income Tax (MTD for Income Tax) becomes mandatory for sole traders and landlords whose qualifying income is over £50,000.
Most associates clear that figure comfortably, so this almost certainly means you. Instead of one Self Assessment return a year, you'll keep digital records and send HMRC quarterly updates through compatible software.
This guide explains who's caught, when, what "qualifying income" actually means for a dentist, and the practical steps to get ready. We've kept it specific to associates, including how your NHS pension and limited company set-up affect things.
It's written for self-employed associate dentists in England, Wales and Northern Ireland. If you trade through a limited company, the picture is different, and we'll flag exactly where.
Do associate dentists have to use Making Tax Digital?
Yes, most will. If you're a self-employed associate registered for Self Assessment and your qualifying income is over £50,000, you must use MTD for Income Tax from 6 April 2026.
Associate dentists are taxed as self-employed individuals. HMRC withdrew its long-standing dental associate concession (guidance reference ESM4030) from 6 April 2023, so self-employed status now rests on the ordinary employment-status tests rather than an automatic concession. Where you're genuinely self-employed and registered for Self Assessment, MTD for Income Tax applies to you on the same timetable as any other sole trader.
The trigger is your income from self-employment and property, not whether your work is NHS or private. Both count.
What does "qualifying income" mean for a dentist?
This is the part dentists most often get wrong, so it's worth being precise.
Qualifying income is your total gross income from self-employment and property in a tax year. HMRC is explicit that it assesses your gross income, meaning income before you deduct expenses, also called your turnover. It is not your profit.
For a typical associate, that means the gross fees you receive under your associate agreement, before lab bills, your share of practice deductions, professional costs or anything else comes off. If you also let a property, that rental income is added on top.
HMRC works your figure out from the Self Assessment tax return you submitted in the previous tax year. So for the first phase, it looks at your 2024/25 return.
Two things follow from "gross, not profit":
- A dentist with £90,000 of gross fees but £55,000 of taxable profit is judged on the £90,000, not the £55,000.
- Income that comes to you as salary (through PAYE) is not self-employment income and does not count towards qualifying income.
When do I have to start, and at what income level?
MTD for Income Tax is being phased in by income band. The thresholds are based on gross qualifying income, and each phase looks back at a specific tax year's return.
| Phase | You must start | Qualifying income over | Income year HMRC checks |
|---|---|---|---|
| 1 | 6 April 2026 | £50,000 | 2024/25 |
| 2 | 6 April 2027 | £30,000 | 2025/26 |
| 3 | 6 April 2028 | £20,000 | 2026/27 |
So if your 2024/25 gross self-employment and property income was over £50,000, you're in the first wave from April 2026. If you were just under in 2024/25 but cross £30,000 in 2025/26, you join a year later.
HMRC says it will write to people it believes are caught, but you remain responsible for checking your own position. Don't wait for a letter. You can confirm your status using HMRC's online tool, "Check if you're eligible for Making Tax Digital for Income Tax".
One useful detail: you don't start using MTD until after you've submitted your first Self Assessment return. Partnerships are not yet mandated, and HMRC has said it will set out their timeline later.
What will MTD for Income Tax actually require?
Three things, in plain terms.
1. Keep digital records. You must create and store digital records of your self-employment (and any property) income and expenses. A shoebox of receipts and a spreadsheet you tidy up in January won't meet the rules.
2. Send quarterly updates. Four times a year, you send HMRC a summary of your income and expenses to date, through compatible software.
3. Finalise the year. After the fourth quarter, you make a final declaration through your software, replacing the old Self Assessment return. This is where you confirm your figures, claim reliefs and report anything else, such as your NHS pension contributions.
You'll need software that works with MTD for Income Tax. We won't name or rank products here, but the key is that it must be HMRC-recognised and able to send both quarterly updates and the final declaration. If you'd like help with the bookkeeping side, our bookkeeping services are built to keep associate records MTD-ready throughout the year.
What are the quarterly update deadlines?
The standard quarters follow the tax year. Each update is cumulative, so it covers the year to date, which means you can correct an earlier figure in a later update without resending.
| Quarter | Period covered | Submission deadline |
|---|---|---|
| 1 | 6 April to 5 July | 7 August |
| 2 | 6 April to 5 October | 7 November |
| 3 | 6 April to 5 January | 7 February |
| 4 | 6 April to 5 April | 7 May (following tax year) |
If your records run to month-end, you can elect to use calendar quarters instead (1 April to 30 June, and so on), with the same four deadlines.
The final declaration, which replaces your Self Assessment return, is still due by 31 January after the tax year. Your tax payment dates don't change either: balancing payment by 31 January, with payments on account on 31 January and 31 July where they apply.
Illustrative example: an associate on £72,000
Illustrative example. Aanya is a self-employed associate. Her 2024/25 Self Assessment return showed £72,000 of gross associate fees and no property income.
Because her qualifying income is over £50,000 and is judged on the gross £72,000 (not her profit after lab fees and other costs), she's mandated into MTD for Income Tax from 6 April 2026.
From that date her year looks like this:
- Records of fees and expenses kept digitally as she goes.
- Quarterly updates due 7 August 2026, 7 November 2026, 7 February 2027 and 7 May 2027.
- A final declaration by 31 January 2028 for the 2026/27 tax year, where she claims her allowable costs and reports her NHS pension position.
Her income tax and Class 4 National Insurance are still worked out on her profit, not her turnover. For 2025/26, Class 4 NIC is charged at 6% on profits between £12,570 and £50,270, then 2% above £50,270. The MTD change is about how she reports, not a new tax. To sense-check what you'll owe on your profit, try our self-employed tax calculator.
How does my NHS pension and superannuation fit in?
This trips up a lot of associates, so let's separate the two issues.
Does superannuation affect my qualifying income? No. Qualifying income is gross self-employment and property income. Your NHS pension contributions are a deduction, not income, so they don't change whether you're over the £50,000 line.
Does MTD change how I report superannuation? The mechanism, not the principle. NHS Pension Scheme superannuation contributions remain an allowable deduction in computing your taxable profit (the long-standing treatment under HMRC's Business Income Manual at BIM54020). Under MTD you still report them, but you do it at the final declaration stage in your software rather than on a paper return.
In practice, your contribution figures flow from your SD86C superannuation certificate, which the NHS Business Services Authority issues through Compass after your Annual Reconciliation Report (typically around the end of July). Keep that certificate to hand for your year-end finalisation, exactly as you do now.
The MTD timetable also doesn't touch separate pensions admin such as your annual allowance position, NHS "Scheme Pays" elections or the McCloud remedy. Those run on their own NHS and HMRC processes and deadlines.
What if I work through a limited company?
If you provide your associate or locum services through your own limited company, you are not within MTD for Income Tax for that company income. MTD for Income Tax applies to sole traders and landlords. A limited company reports through Corporation Tax and its own filing rules.
There's a knock-on point worth knowing: associates and locums who work through a limited company are excluded from the NHS Pension Scheme, because scheme membership attaches to the individual practitioner, not a company. That's a significant trade-off to weigh, and it's a decision to take with proper advice rather than purely to sidestep MTD.
If you're weighing sole trader against limited company, our tax advice for associate dentists walks through the wider picture.
What are the penalties if I get it wrong?
Late submission penalties for MTD for Income Tax are points-based. You get one penalty point each time you miss a quarterly update or final declaration deadline. When you reach 4 points, you receive a £200 penalty, with a further £200 for each later miss.
Points below the threshold drop off automatically 24 months after the missed deadline. Once you hit 4 points, you have to clear them by submitting on time for 12 months and bringing any outstanding submissions from the previous 24 months up to date.
There's an important easement for the first year: HMRC has confirmed there are no penalties for missing a quarterly update deadline in the 2026/27 tax year. You must still keep digital records and send the updates, because you can't make your final declaration without them, but the quarterly points won't bite in year one.
Late payment of tax is separate and is not points-based, so pay on time regardless.
Can I get an exemption?
Possibly, but the bar is high. The main route is being "digitally excluded", for example where it isn't reasonably practicable for you to use compatible software because of age, disability, location with no reliable internet, or religious grounds.
You apply by contacting HMRC, and it aims to respond within 28 calendar days. Being busy, or simply preferring the old system, is not a ground for exemption. If you think you genuinely qualify, apply early rather than assuming.
Your MTD readiness checklist
A short list to work through before April 2026:
- Check your 2024/25 gross self-employment and property income against the £50,000 line.
- Use HMRC's online eligibility checker to confirm your start date.
- Choose MTD-compatible software (or ask your accountant to).
- Move your record-keeping to digital now, so quarter one isn't a scramble.
- Diarise the four quarterly deadlines: 7 August, 7 November, 7 February, 7 May.
- Keep your SD86C certificate ready for the year-end final declaration.
- File your final outstanding Self Assessment return as normal first.
Getting your books in order before the first quarter is the single biggest time-saver. Our Self Assessment service is moving associates onto MTD-ready workflows now, so the switch in April 2026 is a non-event rather than a deadline panic.
Want it handled end to end? Book a free 20-minute call with a Zmartly accountant and we'll map your MTD start date, software and quarterly calendar to your associate income.
Frequently asked questions
Do I still file a Self Assessment tax return under MTD?
Not in the same way. Once you're in MTD for Income Tax, the annual Self Assessment return is replaced by quarterly updates plus a final declaration made through your software. You still finalise the year by 31 January, and your payment dates are unchanged.
Is the £50,000 threshold based on my profit or my turnover?
Turnover. HMRC assesses your gross income before expenses, combining self-employment and property. An associate with gross fees over £50,000 is caught even if profit after costs is lower.
Does my NHS salary or PAYE income count towards the threshold?
No. Qualifying income is self-employment and property income only. Money paid to you through PAYE as employment income does not count towards the £50,000 figure.
I'm just under £50,000. Am I safe?
Only until the threshold drops. From April 2027 it falls to £30,000 of qualifying income, and from April 2028 to £20,000, each judged on the relevant earlier year's return. Most associates will be in scope within these three phases.
What happens to my superannuation reporting under MTD?
It still counts as an allowable deduction against your profit, in line with HMRC's BIM54020. Under MTD you report it at the final declaration stage using your SD86C certificate from the NHS Business Services Authority, rather than on a paper return.
Are there penalties in the first year?
HMRC has confirmed no penalties for missing quarterly update deadlines in 2026/27. You must still keep digital records and submit updates, and late payment penalties still apply, so don't treat year one as optional.
