Going self-employed as a dental associate? What to know before day one

Do I need to register with HMRC when I go self-employed?

Dentists tend to move into self-employment at different points in their careers. For some, it may come after completing foundation training, or serve as a way of moving on from a salaried NHS role, while others may simply be joining a new practice as an associate. While there is no fixed date when the transition should take place, many newly qualified dentists start associate roles around August or September, once foundation training finishes for the year.

Whatever point you start, the deadline is the same: you must register with HMRC Self-Assessment before the end of your first tax year.

E.g. If you plan to go self-employed from September 2026, the deadline to register is 5 October 2027.

The process is fairly simple to do online via GOV.UK, and HMRC will issue you with a Unique Tax Reference (UTR) upon registering. The UTR will be used to identify you for self-assessment, as well as linking your tax filings and payments.

This process can also be done by an accountant depending on your preference.

What is a “payment on account” and why will my first tax bill be larger than expected?

For many newly self-employed associates, the January after their first-year filing can be a financial shock. That’s because HMRC doesn’t just collect the tax you already owe, but also takes advance payments toward the following year’s bill, known as payments on account.

Once you file your first Self-Assessment return, HMRC uses that bill to estimate what you’ll owe next year. You pay that estimate in two equal instalments: half by 31 January and half by 31 July.

One of the challenges with payments on account is that they’re based on your previous year’s tax liability. For many associates, the first tax return covers less than a full year of self-employment, so the payments on account HMRC expects can be too low for the following year. This often leads to a much larger balancing payment the next January. Forward planning is essential to avoid this.

What this means in practice

If you start self-employment in September 2026, your first tax return is due by 31 January 2028. Because it’s your first filing, no advance payments have been made yet, so that bill will include:

• Your full 2026/27 tax liability
• A first payment on account (50% of that bill) as an advance toward 2027/28

So, if your first-year tax bill is £2,800, you won’t just pay £2,800 in January; you’ll pay £4,200, with a further £1,400 due in July.

The simple fix: start saving from day one

Setting aside 25–30% of each monthly payment into a dedicated savings account from September 2026 ensures that, by January 2028, sufficient funds are available to meet the balancing payment.

The exact proportion you should set aside will depend on your tax position. For example, many associates in their first year of self-assessment (SA) will fall within the basic rate band (20%), but may move into the higher rate band (40%) in their second year, assuming no additional income streams.

If other income is present, your effective tax rate may differ, and your savings percentage should be adjusted accordingly.

A specialist dental accountant can calculate your payments on account accurately and assist with forecasting any adjustments needed if your income changes.

Am I definitely self-employed? Why your contract matters more than you think

If you are a dental associate, you have likely always assumed you are self-employed. This assumption became considerably riskier in April 2023, when HMRC withdrew the automatic concession that treated BDA/DPA agreement holders as self-employed by default.

Your employment status is no longer determined by a standard template. It is now assessed on the basis of your actual working relationship, using the following three tests:

• Control: Who decides how and when you work clinically?
• Substitution: Can you send a qualified locum in your place if you are unavailable?
• Financial risk: Do you personally bear lab fees and indemnity costs?

If your working arrangements do not genuinely satisfy these tests, you are at risk of reclassification as an employee or worker for tax purposes. In such cases, HMRC can issue backdated tax and National Insurance bills covering up to four years where reasonable care was taken, six years in cases of carelessness, and up to 20 years if the position is deemed to have been taken deliberately.

The most prudent course of action is to have your associate agreement reviewed by a specialist dental accountant before HMRC initiates its own enquiry. A dental tax specialist can assess your contract and actual working practices against these tests and advise whether your current status is legitimate.

You can also use HMRC’s self-check tool, CEST (Check Employment Status for Tax), to obtain HMRC’s view based on your specific circumstances, although professional advice remains advisable in borderline or complex cases.

Do I need a specialist dental accountant?

Dental accounts involve several sector-specific nuances, including accurate revenue recognition, separate reporting of NHS and private income, GDC-related expenses, NHS Pension Scheme considerations, and UDA reconciliations.

A NASDAL-accredited accountant (a member of the National Association of Specialist Dental Accountants and Lawyers) has demonstrated expertise in these areas and understands the particular compliance and tax issues that affect dental practices.

The cost of specialist advice is itself a deductible expense and is typically far outweighed by the tax savings, cash-flow optimisation, and errors it helps you avoid.

Our specialist dental accountants will support you throughout the process and can provide the following services:

• Assistance with your HMRC registration
• Advice on your employment status and associate agreement
• Identification of all allowable expenses
• Preparation and filing of your Self-Assessment return
• Help with budgeting for tax liabilities and payments on account
• Guidance on MTD readiness when it applies
• Guidance on pension contributions and tax relief
• Support with applications for mortgages and other borrowing, including accountant’s references and income confirmations