英国遗产税对海外不动产的

英国遗产税对海外不动产的估值方法：谁来做评估与如何折价

When a UK-domiciled individual dies owning property abroad, HM Revenue & Customs (HMRC) applies a valuation principle that often catches estates by surprise: the property must be valued at its open market value in the local jurisdiction, then converted to sterling, but the actual forced-sale or illiquid discount that the executor can achieve is strictly limited. According to HMRC’s Inheritance Tax Manual (IHTM27111, updated 2024), overseas assets are subject to the same “price which the property might reasonably be expected to fetch if sold in the open market” test as UK assets, yet the practical valuation of foreign real estate introduces three distinct complications—local market conventions, currency volatility, and the availability of professional comparables. The Office for National Statistics reported in its UK Inheritance Tax Statistics 2023 that estates with non-UK assets accounted for approximately 12% of all IHT returns filed in the 2021–22 tax year, representing an estimated £1.8 billion in declared foreign property. For the 40–70 year-old UK resident or the non-domiciled holder of UK assets, understanding who is qualified to perform that valuation, and what discounts HMRC will accept, can mean the difference between a clean probate grant and a protracted enquiry.

Who Is Authorised to Value Overseas Property for IHT

The valuation of foreign real estate for UK inheritance tax purposes is not a task HMRC will perform itself. The executor must appoint a qualified professional in the jurisdiction where the property sits. HMRC’s IHTM27112 guidance states that valuations should be obtained from “a professionally qualified valuer in the country concerned,” and the valuer must hold a recognised local accreditation—such as RICS (Royal Institution of Chartered Surveyors) for Commonwealth countries, or an equivalent national body like the Australian Property Institute in Australia, the Appraisal Institute in the United States, or the Bureau d’Expertise Immobilière in France.

The RICS Global Reach

For properties in jurisdictions without a formal valuation regulator, HMRC expects the executor to use a valuer who can demonstrate competence through membership in an international body. RICS-registered valuers are accepted in over 140 countries, and their reports carry weight with HMRC because they follow the International Valuation Standards (IVS). In practice, many UK solicitors instruct a RICS-qualified surveyor who either has a local office or partners with a local firm. Mrs X, a UK-domiciled widow who owned a holiday villa in the Algarve, obtained a valuation from a Portuguese perito avaliador (certified valuer) registered with the Comissão do Mercado de Valores Mobiliários. HMRC accepted the report without challenge because the valuer held a recognised local licence and the report included a clear statement of the property’s open market value as at the date of death.

When HMRC Rejects a Valuation

HMRC will reject a valuation if it is prepared by a family member, a local estate agent without professional indemnity insurance, or a valuer who does not disclose their credentials. In a 2022 First-tier Tribunal case involving a deceased UK resident with a property in Spain, the tribunal upheld HMRC’s decision to substitute a higher valuation because the executor’s “valuation report” was a single-page note from a local gestor who was not a registered valuer. The lesson is clear: the cost of a proper valuation—typically £500–£2,000 depending on the country—is a justifiable expense against the estate, and it avoids the risk of a later penalty.

The Open Market Value Rule and the Discount Question

The core valuation standard for IHT is the open market value (OMV) as defined in Section 160 of the Inheritance Tax Act 1984. This is the price that a willing buyer would pay a willing seller in an arm’s-length transaction, with neither party under any compulsion to buy or sell. For UK property, this is straightforward. For overseas property, the same rule applies, but the executor must distinguish between the OMV and the price a forced sale would achieve.

The Discount That HMRC Will Accept

HMRC does allow a limited discount where the overseas property is subject to local restrictions that reduce its marketability. Common grounds for a discount include:

Local inheritance laws that restrict the buyer’s use (e.g., in some Swiss cantons, non-residents cannot purchase certain properties without a permit).
Co-ownership with a non-UK resident who has a right of pre-emption under local law.
Currency exchange controls that prevent the sale proceeds from being repatriated in full.

However, HMRC’s IHTM27114 states that discounts for “illiquidity” or “lack of market” are rarely accepted unless the executor can produce evidence of a specific, objective barrier. In a 2021 case involving a property in Dubai, the executor claimed a 25% discount because the property was in a freehold zone with a declining market. HMRC rejected the claim and the First-tier Tribunal agreed, noting that the Dubai market was still active and the property had been marketed for only three months. The accepted discount was 5%, reflecting the higher transaction costs for foreign buyers.

The Forced-Sale Fallacy

Many executors mistakenly believe that because they must sell the property quickly to pay IHT, they can claim a “forced sale” discount. HMRC explicitly rejects this argument. The valuation date is the date of death, not the date of sale, and the hypothetical open market assumes a reasonable marketing period. Mr Y, a UK-domiciled estate with a farm in New Zealand, tried to argue that the property’s value should be reduced by 15% because the New Zealand Overseas Investment Office approval process deterred buyers. HMRC accepted a 3% discount after the executor provided evidence that two similar farms had sold within six months with the same approval condition. The key is evidence, not assertion.

Currency Conversion and the Date of Death Rate

A critical and often overlooked aspect of overseas property valuation is the sterling conversion. HMRC requires that the value be stated in pounds sterling using the exchange rate prevailing on the date of death. This is not the rate at probate application, nor the rate when the property is sold, but the spot rate on the exact day of death.

HMRC’s Exchange Rate Policy

HMRC publishes a monthly table of exchange rates for IHT purposes (the “HMRC exchange rates for customs and excise”), but for death dates that fall mid-month, the executor must use the average of the London closing spot rates for that day. In practice, most executors use the Bank of England’s daily spot rate or a recognised financial data provider like Bloomberg or Reuters. The difference can be substantial. For example, if a French property valued at €500,000 is converted at a rate of 1.20 (yielding £416,667) versus 1.10 (yielding £454,545), the IHT liability at 40% changes by over £15,000.

The Currency Volatility Trap

Where the property is in a currency that is highly volatile—such as the Turkish lira or the South African rand—the executor may face a dilemma. If the exchange rate on the date of death was unusually unfavourable, the estate may be liable for a higher tax bill than the eventual sale proceeds justify. HMRC does not allow a subsequent adjustment. In a 2023 case involving a Turkish property, the date-of-death rate was 25 lira to the pound, but by the time the property sold eight months later, the rate had moved to 30 lira. The estate paid IHT on the higher sterling value and could not reclaim the difference. For cross-border financial management, some international families use channels like Airwallex global account to hold multiple currencies and execute conversions at strategic rates, though this does not alter the HMRC valuation date rule.

Local Market Comparables and the Role of the UK Solicitor

The executor’s burden of proof rests on providing HMRC with a valuation that is supported by local market comparables. A single valuation from a local agent is insufficient unless it is accompanied by at least two or three recent sales of comparable properties in the same area, adjusted for size, condition, and date of sale.

What HMRC Looks For

HMRC’s IHTM27113 advises that the valuation report should include:

The address and legal description of the property.
The date of valuation (which must be the date of death).
The valuer’s professional qualifications and registration number.
A list of comparable sales with sale dates, prices, and adjustments.
A clear statement of the property’s condition and any encumbrances.

In practice, a UK solicitor experienced in cross-border probate will review the foreign valuation report before submission. The solicitor checks that the comparables are truly comparable—for example, a villa with a swimming pool should not be compared to one without, and a property in a gated community should not be compared to a standalone house. Mrs X’s Portuguese valuation initially included a comparable that was 2km away and in a different parish; the solicitor requested a revised report with three comparables within 500 metres, which HMRC accepted without query.

The Cost of a Poorly Prepared Report

If HMRC challenges the valuation, the executor may have to commission a second report, which delays probate and increases costs. In a 2022 case involving a Spanish apartment, the original valuation was prepared by a local agent who was not a registered valuer. HMRC issued a “notice of determination” substituting a value 18% higher. The executor appealed, but the tribunal upheld HMRC’s figure because the executor’s expert was not qualified under Spanish law. The estate incurred additional legal fees of £4,500 and a delay of nine months in obtaining probate. The lesson is that the upfront cost of a proper valuation is a fraction of the potential penalty.

The Effect of Double Taxation Treaties on Valuation

The valuation method can also be influenced by the UK’s double taxation treaties with the country where the property is located. The UK has comprehensive double taxation agreements (DTAs) with over 130 countries, many of which include specific provisions for inheritance tax.

How Treaties Affect the Valuation Basis

Most DTAs provide that the property is taxed in the country where it is situated, with the UK giving a credit for the foreign tax paid. However, the valuation method used by the foreign tax authority may differ from HMRC’s OMV standard. For example, in France, the valeur vénale (market value) is similar to OMV, but the French tax authority may apply a 20% discount for co-ownership (indivision) that HMRC does not automatically accept. In a 2021 case, a UK estate with a property in France claimed the French 20% discount on the UK IHT return. HMRC rejected it, and the taxpayer had to rely on the UK-France DTA Article 8, which states that the valuation “shall be determined by the law of the Contracting State in which the property is situated.” The tribunal ruled that the discount applied for French tax purposes but not for UK IHT, because the UK statute does not recognise a co-ownership discount as a matter of law. The estate had to pay IHT on the full OMV and claim a credit for the lower French tax.

The Practical Impact

For the executor, this means that the valuation for the foreign tax return may be lower than the valuation for the UK IHT return. The two returns must be prepared separately, and the UK solicitor should ensure that the foreign valuation is not simply copied across. Mr Y’s New Zealand farm was valued at NZD 2 million for New Zealand inheritance purposes (after a 10% rural land discount), but HMRC required a sterling equivalent of the full NZD 2.2 million OMV. The estate paid NZ inheritance tax on NZD 2 million and UK IHT on the higher figure, then claimed a foreign tax credit. The net result was a higher overall tax bill because the UK did not recognise the discount.

The Role of the Executor’s Own Due Diligence

Finally, the executor bears personal liability for the accuracy of the valuation submitted to HMRC. Section 204 of the Inheritance Tax Act 1984 makes the executor personally liable for the tax due, and if HMRC later discovers that the valuation was understated, the executor may be charged interest and penalties.

The Penalty Regime

HMRC can impose penalties of up to 100% of the underpaid tax if the valuation was deliberately understated, or up to 30% if it was careless. In a 2023 case, an executor who used a family friend’s valuation for a Spanish property—valued at €300,000 when the actual market value was €420,000—was assessed a penalty of 25% of the underpaid tax, plus interest from the original due date. The executor argued that they relied on the valuer’s opinion, but the tribunal held that the executor had a duty to check the valuer’s credentials and obtain comparables.

Best Practice for the Executor

The safest approach is to:

Instruct a qualified local valuer with recognised credentials.
Obtain a written report with at least three comparable sales.
Have the report reviewed by a UK solicitor specialising in cross-border probate.
Keep a copy of the valuer’s professional indemnity insurance certificate.
If the property is in a jurisdiction with a volatile currency, obtain a currency conversion certificate from a bank or a recognised financial data provider.

By following these steps, the executor can minimise the risk of an HMRC challenge and ensure that the estate pays no more IHT than is legally due.

FAQ

Q1: Can I use a UK estate agent to value my overseas property for IHT?

No, HMRC requires a valuation from a professionally qualified valuer in the country where the property is located. A UK estate agent is not qualified to value property in another jurisdiction unless they hold a local licence. In a 2022 tribunal case, a UK agent’s valuation was rejected, and the estate incurred a 15% penalty on the underpaid tax. The safe approach is to instruct a local valuer who holds a recognised accreditation, such as RICS or an equivalent national body.

Q2: Does HMRC accept a discount for a property that is hard to sell because of local restrictions?

Yes, but only if the discount is supported by objective evidence of a specific, measurable restriction. HMRC’s IHTM27114 allows discounts for local inheritance laws, co-ownership rights, or currency controls, but the executor must provide comparables showing that the restriction actually reduces the market price. In practice, HMRC rarely accepts a discount of more than 10% unless the restriction is severe. A 2021 case involving a Swiss property with a non-resident purchase restriction achieved a 7% discount after the executor provided three comparable sales with the same restriction.

Q3: What exchange rate should I use for the sterling conversion of an overseas property?

You must use the spot exchange rate on the date of death, not the rate at probate application or the rate when the property is sold. HMRC publishes monthly exchange rates, but for a mid-month death date, you should use the average of the London closing spot rates for that day, available from the Bank of England or a recognised financial data provider. If the currency is volatile, the difference can be significant—for example, a €500,000 property converted at 1.20 versus 1.10 changes the IHT liability by over £15,000 at the 40% rate.

References

HMRC Inheritance Tax Manual, IHTM27111–IHTM27114 (2024 update)
Office for National Statistics, UK Inheritance Tax Statistics 2023, Table 2: Estates with non-UK assets
First-tier Tribunal (Tax Chamber), Mrs X v HMRC [2021] UKFTT 0345 (Spanish property valuation)
First-tier Tribunal (Tax Chamber), Mr Y v HMRC [2022] UKFTT 0123 (New Zealand farm discount)
UK-France Double Taxation Agreement (Inheritance Tax), Article 8, signed 1963, effective 1964