An expense does not save you its full value. It saves you your marginal rate, which for a self-employed associate is income tax plus Class 4 National Insurance:
So the GDC annual retention fee of £698 for dentists in 2026 costs a basic-rate associate £516.52 after relief, a higher-rate associate £404.84, and an associate in the £100,000 to £125,140 band just £265.24. The same claim, three very different prices.
Travel from home to your regular practice is ordinary commuting. It is not allowable, however far it is and however unsocial the hours. What can qualify is travel between workplaces on the same day, or travel to a genuinely temporary workplace — a short-term locum booking, a course, a hospital session.
If you use the simplified flat rate rather than actual costs, the rate for cars and goods vehicles rose on 6 April 2026 to 55p per mile for the first 10,000 business miles in the tax year, from 45p previously. It remains 25p per mile above 10,000 miles, and 24p for motorcycles.
Put figures on it. An associate splitting the week between two practices 18 miles apart, driving between them twice a week for 46 working weeks, does 1,656 qualifying business miles. At 55p that is a claim of £910.80 — worth £382.54 to a higher-rate associate. The same associate's 36-mile daily round trip from home to their main practice is worth nothing at all. The difference is entirely in which journey it is, which is why the mileage log matters: it is the first thing HMRC asks for, and the only thing that settles the point.
The cash basis is now the default method for sole traders, so unless you elect out on your tax return you are taxed on money in and money out rather than on invoiced income. For equipment, that usually simplifies things: most tools and equipment you buy outright are deducted in full in the year you pay for them, with cars the notable exception.
If you use traditional accruals accounting instead, equipment goes through capital allowances, and the Annual Investment Allowance gives 100% relief on up to £1 million of qualifying plant and machinery a year. Either way, a £3,200 set of loupes bought this year is almost always relieved this year — the difference is the mechanism, not the outcome. It matters more if you have uneven income across tax years, or if you are weighing up incorporating, where the treatment differs again.
Two routes. The simplified flat rate is £10 a month if you work 25 to 50 hours a month at home, £18 for 51 to 100 hours, and £26 for 101 hours or more — a maximum of £312 a year, requiring no calculation and no evidence beyond the hours. Or you apportion actual costs by rooms and time, which produces a larger claim for most associates but needs the workings kept. Pick one, and keep the basis consistent year to year.
Under a standard associate agreement, lab fees are deducted from your gross before you are paid, so they are effectively already relieved — claiming them again is a straightforward duplication. Materials, nursing support, surgery costs, decontamination and the practice's own software belong to the practice, not to you. Claiming practice-side costs is one of the fastest ways to turn a routine return into an enquiry, because the numbers do not reconcile to the pay statements the practice holds.
Making Tax Digital for Income Tax began on 6 April 2026 for sole traders and landlords whose qualifying income for 2024/25 was over £50,000, which covers most full-time associates. That means digital records and quarterly updates to HMRC rather than one annual reconstruction from a carrier bag of receipts. The threshold falls to £30,000 from 6 April 2027 and to £20,000 from 6 April 2028.
The practical consequence for expenses is that the shoebox method has stopped working: you now need the mileage log, the receipts and the categorisation as you go. Our MTD guide for dentists sets out what to have in place, and the associate tax guide covers how the quarterly updates fit around payments on account.
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Not for ordinary home-to-practice commuting, which is never allowable regardless of distance or how unsocial the hours are. What does qualify is travel between two workplaces on the same day, or travel to a genuinely temporary workplace such as a short locum booking, a course or a hospital session. If you use the simplified flat rate, cars and goods vehicles are claimed at 55p per mile for the first 10,000 business miles from 6 April 2026, then 25p above that, with motorcycles at 24p. Keep a mileage log recording date, route and purpose — it is the first thing HMRC asks for and the only thing that settles the point.
It depends on whether the course maintains skills you already have or gives you a new one. CPD that updates or maintains your existing scope of practice is allowable revenue expenditure. Training that qualifies you in a genuinely new specialism is usually treated as capital, and capital expenditure on your own skills does not attract relief. Large implant, orthodontic and sedation courses sit right on that line, and the amounts are big enough that guessing is expensive — the fee, the travel and the clinical days you give up all ride on the answer. Take advice before you book rather than after you have paid.
Yes. The GDC annual retention fee and your professional indemnity premium are among the most reliable claims an associate makes, alongside subscriptions to professional bodies on HMRC's approved List 3, which includes the BDA. The GDC fee for dentists is £698 for 2026, due by 31 December, with no reduction for part-time working; dental care professionals pay £108, due by 31 July. Remember that the saving is your marginal rate rather than the full amount: £698 is worth £293.16 to a higher-rate associate and £181.48 to a basic-rate one.
It saves you your marginal rate, not its face value. On profits between £12,570 and £50,270 that is 20% income tax plus 6% Class 4 National Insurance, so 26%. Between £50,270 and £100,000 it is 40% plus 2%, so 42%. Between £100,000 and £125,140 the personal allowance is withdrawn at £1 for every £2 of income, producing an effective 60% income tax rate plus 2% Class 4, so 62% — the band where a forgotten claim costs the most. Above £125,140 it is 45% plus 2%, so 47%. A £1,000 claim therefore saves between £260 and £620 depending purely on where your profits sit.
There are two routes and you should pick one. The simplified flat rate is £10 a month if you work 25 to 50 hours a month at home, £18 a month for 51 to 100 hours, and £26 a month for 101 hours or more — a maximum of £312 a year, needing no calculation beyond a record of the hours. Alternatively you apportion your actual household costs by the number of rooms used and the time they are used for work, which produces a bigger claim for most associates but requires the workings to be kept and repeated each year. Be consistent: switching method annually to whichever gives more invites questions.
Most full-time associates do. Making Tax Digital for Income Tax started on 6 April 2026 for sole traders and landlords whose qualifying income for the 2024/25 tax year exceeded £50,000, and qualifying income means gross practice income before expenses rather than profit. The threshold drops to £30,000 from 6 April 2027 and £20,000 from 6 April 2028, so part-time and newly qualified associates are drawn in over the following two years. In practice it means keeping digital records and sending HMRC quarterly updates, which ends the annual reconstruction of a year's expenses from a carrier bag of receipts.
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