Every number on this site can be traced back to a published source. This page sets out what those sources are, how the figures are built, and where the method has limits worth knowing about.
Sources
Price Paid Data, HM Land Registry
The spine of the archive. It records the price paid for property sold in England and Wales, the date of transfer, the address, the property type, whether it was a new build, and whether the title is freehold or leasehold. It is published monthly under the Open Government Licence v3.0. Sales are recorded on completion and can take several weeks to appear, so the most recent weeks are always incomplete.
Energy Performance Certificates
EPC records supply the floor area used for every price per square metre on the site. They are matched to sales on postcode and a normalised address. The match is conservative: where it is not confident, no floor area is used and no price per square metre is published.
The certificate register is also used on its own, without any sale attached. It covers roughly 7.7 million homes across 1.2 million postcodes — including a great many that have never changed hands — which is why the “how big homes are here” figures on each area page rest on a far larger sample than the sold record could ever provide. Those figures describe the housing stock, not the market.
ONS CPIH
The Consumer Prices Index including owner occupiers’ housing costs is the index used for every real-terms figure. CPIH is the right choice here precisely because it includes housing costs, which the headline CPI leaves out.
Local context: affordability, rent and crime
Three further public datasets sit alongside the sold record, joined to it through the postcode district’s local authority. The ONS affordability ratio compares the median local house price with median local earnings. The ONS Price Index of Private Rents supplies mean rents, which turn a hypothetical yield into a measured one. police.uk supplies every recorded street-level crime within a mile of a district centre.
Each carries a limit that is printed on the page rather than hidden here. Affordability and rent are published for a whole local authority, so a single street inherits its council’s figure and not its own. A crime count is not a rate: a district with a station and a high street records more crime than a residential one of the same size. And several police forces do not supply street-level data at all — where that is the case the page says so instead of showing a zero.
Every dataset, its publisher and its licence is listed on the data sources page.
Why the median, not the average
A handful of very expensive sales pulls a mean upwards and away from anything a typical buyer experienced. The median — the middle sale, with as many above as below — is far more stable, and is what every headline figure on this site uses.
The sales that are left out
HM Land Registry marks some entries as additional price paid records rather than standard sales. They include repossessions, transfers between companies or family members, portfolio moves and sales at a discount such as right to buy. They are genuine records, but they are not open-market prices, and roughly one entry in five falls into this group. Every median, chart and ranking on this site is built from standard sales only. The count of excluded transfers is printed on each area page so the omission is visible rather than silent.
Tenure and new build
Leasehold and freehold sales are counted separately on every area page, as are new builds. A single median that mixes a leasehold flat with a freehold house describes neither. Where the gap between them is large, it is usually property type doing the work rather than tenure itself — the pages say so rather than leaving the reader to guess.
Publishing thresholds
An area only gets a page once it has enough recorded sales for a median to mean something: 100 sales for a town, 50 for a postcode district, 30 for a postcode sector, and 5 for a street. Addresses need two recorded sales before they get a page of their own, because a single sale is not a history. Areas below the threshold are simply absent — a thin page with a confident-looking number would be worse than no page.
The same bar applies inside a page. A year with fewer than five recorded sales in the area is left out of the trend line and out of every comparison built on it. Two sales in a year is not a market, and one unusual house would otherwise become a spike that appears to describe the whole street. It is the difference between a chart that reports the record and one that reports its own gaps.
How the real-terms figures work
Each price is multiplied by the ratio of the latest CPIH index value to the value for the year of sale. The result is what that sum of money would buy today. The decade comparison on every page uses the same method at both ends, so cash and real changes are measured across identical periods.
Known limits
- The register is not the whole market. Transfers that are not at arm’s length, right-to-buy sales at a discount, and some commercial transactions all appear, and none of them describe an open-market price.
- Addresses are messy. The same building can be recorded several ways across three decades. Street and address pages group what can be grouped confidently and no more.
- Floor areas are partial. Only a minority of sales can be matched to an EPC, so price per square metre rests on a smaller sample than the median beside it. Each page prints both counts.
- Thin years disappear. Because a year needs five sales before it is plotted, a quiet area’s chart can have gaps. The gaps are honest: the register really does contain nothing usable for those years.
- Mix changes shift medians. A year in which an area sold mostly flats will show a lower median without any individual home losing value. The property-type table on each page exists so this is visible.
- Scotland and Northern Ireland are not covered. They maintain separate registers with different rules.
How often it updates
HM Land Registry publishes Price Paid Data monthly. The archive is rebuilt from the published files, and each page prints the date of the most recent sale it contains.