How to work out what your home is worth from sold prices

There is a version of this you can do yourself, in about five minutes, from data that is already public. Take your floor area, multiply it by the median price per square metre in your postcode district, then widen the answer into a range using the middle 60% of local sales. That is the whole method, and the rest of this piece is about how to do each step properly and what the result does not tell you.

Start with the honest framing. This is a market figure for a home of that size in that area, not a valuation of your home. It knows two things, where the property is and how big it is, and nothing else. It has not seen the kitchen, the lease, the noise from the road or the state of the roof. RealScout does not value individual properties and this article is not an attempt to. What it can do is tell you whether a number someone else has given you sits in a sensible place.

Step 1: find your floor area

Use the internal floor area on the property’s Energy Performance Certificate, because that is the figure the sold-price statistics are built from and you want both sides of the division to mean the same thing. An agent’s floorplan and an EPC do not always measure the same footprint, so a figure from a listing is a reasonable estimate rather than a like-for-like input. The EPC floor area is what it measures and misses in more detail.

Step 2: find your district’s median, and its denominator

Every postcode district has a page here with its median price per square metre and, beside it, the number of matched sales that median rests on. Read both, and read the window: it is 12 months for most districts, but where the sample is too thin to support that it widens to 24, 36 or 60 months, and the page says which. A median built on 600 sales is a description of a market; a median built on 30 is a description of 30 sales. Across England & Wales the median sale in the 12 months to June 2026 went for £3,380/m², from 474,766 matched sales out of 599,244 registered.

Step 3: multiply, then widen it into a range

The multiplication is the easy half and the least useful on its own. A single number implies a precision that a market median cannot support, so take the 20th and 80th percentiles from the same district page and multiply by those too. That gives you the band the middle 60% of local sales actually landed in.

The same arithmetic in a dearer market gives a wider band in cash terms. SW11, Battersea has a median of £9,260/m² over 744 matched sales, running £7,210 to £11,400/m² across the middle 60%, so the same 70 m² spans roughly £505,000 to £798,000. In NE3, Gosforth, at £2,810/m² over 574 matched sales and £2,140 to £3,620/m² across the band, it is about £150,000 to £253,000. Percentage uncertainty is broadly similar; only the pounds change.

The four things this cannot see

Every one of these moves a real sale price and none of them is in the arithmetic, which is why the band matters more than the midpoint.

• Tenure and lease length. Flats and houses trade on different curves, and a short lease is a repair bill with a deadline. Read the tenure split for your district rather than the all-tenure median.
• Condition and newness. A district median blends new-build and resale, and the new-build premium is large in some districts and absent in others.
• Position within the district. Districts are not uniform: one end of a postcode district can trade well above the other, which is what the p20–p80 band is partly measuring.
• Everything specific to the home. The garden, the floor it is on, the view, the extension, the works it needs. This is the part only a person standing in the property can price.

One bias worth knowing, which nobody else publishes

A price per square metre can only be computed for a sale whose address matches a certificate with a usable floor area. So the statistics describe that matched subset, not every sale, and the honest question is whether the subset is representative. Over the last 60 months the median matched sale went for £285,000 against £290,000 for everything else, a ratio of 0.983. The homes carrying a published rate are therefore about 1.7% cheaper at the median than the wider market, which is small, measurable, and worth knowing before you treat the figure as the whole market rather than most of it. The methodology page publishes this ratio nationally and by region.

Then check it against a real person

Use this to arrive informed, not to replace advice. If an agent’s number sits inside your band, the disagreement is about the specific home and that is a conversation worth having. If it sits well outside, ask which of the four things above is doing the work. A figure you can check is a much better starting point than a figure you cannot, and the buyer-side version of this check is the same arithmetic pointed the other way.

Search any postcode district, sector or full postcode to get the two numbers this method needs. Everything above comes from the June 2026 build, rebuilt monthly from HM Land Registry sold prices matched to EPC floor areas, and the underlying figures are free to download from the dataset page.