In short: A retrospective valuation is a RICS Red Book valuation of a property at a date in the past, such as a date of death, 31 March 1982 or the date a lease extension notice was served. It uses only the market evidence and property condition that applied at that date, and is most often needed for capital gains tax, inheritance tax, lease extensions and disputes.
Last reviewed: 31 October 2026 by Patrick Oliver BSc (Hons) MRICS, RICS Registered Valuer.
Need a value at a past date? Tell us the date, the purpose and the property, and we will confirm our fee and the evidence we will need.
Contact us about a retrospective valuationor call 0800 035 6473
A good share of the valuations I prepare are not about what a property is worth today. They are about what it was worth on a particular day, sometimes last month and sometimes more than forty years ago. Accountants, executors, solicitors and leaseholders ask for them because the law fixes the date, and the tax or the premium depends on the figure at that date.
This guide explains when a retrospective valuation is needed, how I approach one, what evidence matters and how to avoid the mistakes that lead HMRC or the other side to challenge the figure. It complements my guides to capital gains tax and inheritance tax valuations, which cover the tax rules in more depth.
What is a retrospective valuation?
A retrospective valuation is a valuation of a property at a specified date in the past, rather than at the date of the report. The valuer asks what the property would have sold for on that day, in the condition it was in then and in the market as it stood then. Everything that happened afterwards, such as a refurbishment, an extension or a market rise, is left out unless the instruction says otherwise.
The basis of value is usually market value, the same basis used for a current valuation. What changes is the evidence: I am looking for sales and market conditions around the valuation date, not today's asking prices.
When do you need a retrospective valuation?
A retrospective valuation is needed whenever tax law, a statute or a court fixes the value at a past date. The most common situations I deal with are set out below.
| Purpose | Valuation date | What it is used for |
|---|---|---|
| Capital gains tax on a property owned since before 1982 | 31 March 1982 | The rebased acquisition cost for working out the gain |
| Capital gains tax on an inherited property | Date of death | The acquisition value for the beneficiary, where no probate value was agreed |
| Capital gains tax on a gift or sale to a connected person | Date of the transfer | Market value instead of the price actually paid |
| Inheritance tax and probate | Date of death | The value of the property in the estate |
| Lease extension or collective enfranchisement | Date the tenant's notice was served | The statutory premium |
| Negligence, dispute or matrimonial claims | Date of the original transaction or agreed date | Evidence of loss, or the value of an asset at a key date |
Since April 2008, the capital gains tax rules treat an asset held on 31 March 1982 as acquired at its market value on that date. For an inherited property, the market value at the date of death is the beneficiary's acquisition value, and where a value was agreed with HMRC for inheritance tax, that agreed figure is normally the one used.
How does a surveyor value a property at a past date?
A surveyor values a property at a past date by reconstructing three things: the property as it was, the market as it was, and the comparable sales that buyers would have looked at then. I follow the same RICS Red Book standards as for a current valuation, and I state the valuation date, the basis of value and every assumption in the report.
- The property as it was. I inspect the property where it still exists, then work back to its condition at the valuation date using photographs, estate agents' particulars, planning and building control records, and what the client or family can tell me. An extension added in 2010 is excluded from a 1982 valuation.
- The market as it was. I use sales of similar properties close to the valuation date, adjusted for time with house price index data for the area where needed.
- The legal position as it was. Tenancies, lease length and planning status at the valuation date all affect the figure. A house let to a protected tenant in 1982 is valued with that tenancy, even if it was later sold with vacant possession.
The valuation should reflect what a buyer could have known at the valuation date. Later events are not used to second-guess the figure, and where I use later evidence at all, for example to confirm a trend, I say so in the report.
What evidence do you need for a 1982 valuation?
A 1982 valuation needs evidence of what the property was like then and what similar properties sold for around that date. Land Registry price-paid data only starts in 1995, so older evidence has to come from other sources.
- Old photographs, sale particulars, surveys, mortgage valuations or insurance schedules for the property itself.
- Planning and building control records, to establish which extensions and conversions came later.
- Contemporary sale prices from local archives, old newspaper property pages and historic house price indices for the region.
- The tenure and any tenancies in place on 31 March 1982.
Where the evidence is thin, I explain how much weight each source carries and why. HMRC is far more likely to accept a reasoned figure with a clear audit trail than a round number with no workings.
Worked example: a house owned since 1978
Illustrative example: the figures below show a typical pattern, not a real case, and ignore costs, reliefs and the annual exempt amount.
A client bought a terraced house in south London in 1978 for £18,000. In 1995 they added a rear extension and a loft conversion. They sold the house in 2026 for £850,000, having let it out for many years, so no private residence relief applies.
| Step | Illustrative figure |
|---|---|
| Market value at 31 March 1982, as the house was then (no extension or loft) | £32,000 |
| Cost of the 1995 extension and loft conversion (allowable improvement expenditure) | £28,000 |
| Sale price, 2026 | £850,000 |
| Gain before costs and reliefs (£850,000 − £32,000 − £28,000) | £790,000 |
The common mistake in this pattern is to value the house in 1982 as it is today, with the extension and loft. That would overstate the 1982 value and understate the gain, and it is exactly the kind of figure HMRC challenges. The improvement costs are claimed separately, not built into the 1982 value.
How do retrospective valuations work for lease extensions?
For a statutory lease extension of a flat under the Leasehold Reform, Housing and Urban Development Act 1993, the premium is assessed at the date the tenant's notice is served on the landlord. If negotiations take a year, the valuation still looks back to that date, so the lease length, the flat's value and the evidence are all taken as they stood on the day the notice was served.
This matters because short leases lose value quickly. A lease that had 81 years left when the notice was served is valued at 81 years, even if it has dropped below 80 by the time the premium is agreed. My guide to the Schedule 13 premium explains the calculation, and the lease extension calculator gives a quick indicative figure.
How do you avoid HMRC challenging a retrospective valuation?
The best way to avoid a challenge is a Red Book valuation from a RICS Registered Valuer that shows its evidence and reasoning. HMRC's Valuation Office Agency reviews property values in tax returns, and a figure without support is the one most likely to be queried.
- Value the right property. The property as it was at the valuation date, with the tenure and tenancies that applied then.
- Use evidence from the right time. Sales around the valuation date, adjusted with care, not today's prices worked backwards.
- Keep the audit trail. Photographs, records and comparables in an appendix make the figure easier to defend.
- Consider a post-transaction check. For capital gains tax, HMRC will check a valuation after the disposal and before you file, using form CG34.
- Mind the deadline. UK residents selling UK residential property with tax to pay must report and pay within 60 days of completion, so instruct the valuation early.
Retrospective valuations: frequently asked questions
Can a property be valued at a date years ago?
Yes. A RICS Registered Valuer can value a property at any past date, including 31 March 1982, by reconstructing its condition then and using sales evidence from around that date.
Do you need to inspect the property for a retrospective valuation?
An inspection is recommended where the property still exists, because it shows the construction, layout and later changes. Some retrospective valuations can be prepared without an inspection, and the report then states that assumption clearly.
Is a probate value the same as a retrospective valuation?
A probate value prepared after the death is a retrospective valuation at the date of death. Where the value was agreed for inheritance tax, beneficiaries normally use that figure as their acquisition value for capital gains tax.
Can I use an estate agent's appraisal instead?
An estate agent's appraisal is a marketing opinion, not a valuation at a fixed past date, and it rarely shows evidence. For tax, lease extensions and disputes, a Red Book valuation from a RICS Registered Valuer is far easier to rely on if the figure is questioned.
How long does a retrospective valuation take?
Most retrospective valuations take one to two weeks after the inspection, depending on how far back the date is and how much historic evidence has to be gathered.
Need a property valued at a past date? Contact us or call 0800 035 6473.
Patrick Oliver BSc (Hons) MRICS, Chartered Surveyor and RICS Registered Valuer, Aston James Associates
This article is general guidance only and is not tax or legal advice. Speak to your accountant or solicitor about your own position.
Recent Comments