What Does a Professional Inheritance Tax Accountant in the UK Do?

Guidance from a Seasoned UK Inheritance Tax Adviser

This piece is written in the voice of a seasoned UK tax adviser with 20+ years of experience, aimed at UK individuals, executors, and families seeking clarity on the role, value, and practical functions of a professional Inheritance Tax accountant.
Understanding the Role of a Professional Inheritance Tax Accountant
In the UK, Inheritance Tax (IHT) remains one of the most misunderstood areas of personal taxation. Despite its name, it isn’t a “death duty” on everyone; rather, it’s a charge on the value of a person’s estate above certain thresholds when they die, and in some cases on significant lifetime gifts.
A professional Inheritance Tax accountant in uk is a specialist who helps individuals, executors, and families navigate the HMRC rules surrounding this complex tax. Their role extends well beyond completing forms; it involves interpreting legislation, applying reliefs, valuing assets, and ensuring that the estate remains fully compliant while avoiding unnecessary tax exposure.
From my two decades advising families across the UK, I’ve seen that even modest estates can quickly become complicated once property, pensions, trusts, or gifts are involved. That’s where a qualified tax accountant adds real value translating intricate HMRC guidance into clear, defensible advice tailored to your personal circumstances.
Core Responsibilities of an Inheritance Tax Accountant
While every case differs, the professional duties of an Inheritance Tax accountants generally fall into four key areas: compliance, valuation, tax reliefs, and planning. Let’s look at each in more detail.
1. Ensuring HMRC Compliance and Timely Reporting
When someone dies, the executors or administrators of their estate are legally responsible for reporting the estate’s value to HMRC and paying any Inheritance Tax due. The accountant’s first task is to determine whether the estate exceeds the nil-rate band currently £325,000 per person for the 2025/26 tax year.
They prepare and submit the required HMRC forms, most commonly:
●IHT400 – the main Inheritance Tax return, required for estates above the threshold, and

●IHT205 – used for simpler estates below the threshold.

The accountant ensures that the valuation and documentation meet HMRC’s strict evidential standards and that deadlines are met. Currently, tax must be paid within six months of the end of the month of death, even if probate hasn’t been granted. Missing that deadline can trigger interest charges and penalties.
An experienced tax adviser helps executors manage those time pressures by creating a detailed timeline, securing instalment options for property-based tax, and liaising directly with HMRC’s Inheritance Tax office on your behalf.
2. Accurate Valuation of the Estate
Proper valuation is the cornerstone of IHT compliance. A professional accountant helps determine the  open market value of every asset at the date of death from family homes and investments to business interests and valuable possessions.
They coordinate with estate agents, surveyors, or valuers when necessary, and ensure that joint ownership, trust-held assets, and insurance pay-outs are treated correctly. Even a small misstep say, undervaluing a property by £50,000 can attract HMRC queries, additional tax, and potential penalties for “careless” reporting.
It’s common practice for accountants to maintain detailed working papers to justify every valuation submitted, giving executors confidence that their estate is defensible under HMRC scrutiny.
3. Applying Allowances and Reliefs to Reduce Liability
An experienced Inheritance Tax accountant doesn’t just report numbers they optimise them. The UK system offers several legitimate reliefs that can dramatically reduce or even eliminate tax liability.
Here are the key allowances and reliefs a professional adviser will assess and apply:
Allowance / Relief 2025/26 Threshold Description
Nil-Rate Band £325,000 per individual Amount of estate exempt from IHT
Residence Nil-Rate Band (RNRB) £175,000 Additional allowance for homes passed to direct descendants
Spouse or Civil Partner Exemption Unlimited Assets left to a UK-domiciled spouse are fully exempt
Business Relief Up to 100% Applies to qualifying business or agricultural assets
Charitable Donations 100% on gifted amount Gifts to UK charities reduce the taxable estate
Small Gifts Exemption £250 per recipient Gifts below this per person per tax year are exempt
Annual Exemption £3,000 per year Gifts up to this limit are excluded from IHT
A qualified accountant ensures that these reliefs are maximised for instance, transferring unused nil-rate bands between spouses or ensuring the residence nil-rate band isn’t lost through poor structuring.

Lifetime Tax Planning vs. Post-Death Compliance
One of the key distinctions a professional Inheritance Tax accountant makes is between proactive lifetime planning and reactive post-death administration.
During a client’s lifetime, the adviser focuses on legitimate planning strategies such as gifting, trusts, business succession, or life insurance structures designed to reduce the eventual IHT burden. The key rule here is the seven-year rule: gifts made more than seven years before death usually fall outside the estate.
After death, the accountant’s focus shifts to reporting accuracy, relief optimisation, and liaison with HMRC. They work hand-in-hand with solicitors handling probate, ensuring financial and legal processes dovetail smoothly.
Here’s how the two areas typically differ:
Stage Main Focus Example Tasks
Lifetime Planning Reducing future IHT liability Structuring gifts, setting up trusts, advising on Business Relief eligibility
Estate Administration Ensuring compliance and efficiency Completing IHT400, calculating tax due, securing instalment arrangements
An experienced adviser often manages both aspects for long-standing clients, ensuring continuity of records and a clear audit trail for HMRC.

Real-World Example: How a Tax Accountant Saves Thousands in IHT
Consider a widowed client in Surrey with an estate worth £900,000, including her home valued at £500,000. Without advice, her executors would face an IHT bill of roughly £90,000 (40% of the £225,000 above her £325,000 nil-rate band and £175,000 residence nil-rate band).
However, with professional input, several key adjustments were made:
●£30,000 in qualifying charitable donations reduced the effective IHT rate from 40% to 36%.

●Transfer of her late husband’s unused nil-rate bands doubled her available exemption.

●Proper valuation of joint assets reduced the taxable estate by £25,000.

Result: the estate’s final IHT bill fell below £10,000, a saving of around £80,000 fully HMRC-compliant, properly evidenced, and stress-free for the executors.
That’s the tangible difference a seasoned Inheritance Tax accountant can make not just by “doing the sums,” but by understanding how to apply reliefs correctly and strategically.

The Importance of Regulation and Professional Oversight
In the UK, Inheritance Tax accountants are typically regulated through professional bodies such as the Institute of Chartered Accountants in England and Wales (ICAEW), the Association of Chartered Certified Accountants (ACCA), or the Chartered Institute of Taxation (CIOT).
These organisations enforce ethical standards, continuous professional development, and compliance with HMRC’s Professional Conduct in Relation to Taxation (PCRT). They also supervise compliance with anti-money laundering (AML) legislation, a critical safeguard given the financial sensitivity of estate administration.
For clients, this means working with a qualified professional provides protection, accountability, and assurance that your adviser operates under a strict code of integrity and competence.
The Human Side of Inheritance Tax Work
Despite the technical nature of IHT, the human element is never lost. A compassionate tax accountant understands that clients often come during emotionally difficult times after a bereavement or during complex family discussions about wealth and fairness.
The best professionals balance technical precision with empathy: explaining complex calculations in plain English, ensuring executors feel supported, and liaising discreetly with HMRC so families can focus on what matters most.
In over 20 years of practice, I’ve seen that the most valued advisers are not just numerically skilled but emotionally intelligent — guiding families through one of life’s most sensitive financial transitions with clarity, transparency, and reassurance.