What HM Land Registry sold data really tells you about local prices

What the dataset contains

• Address, price paid and date of transfer for registered residential sales in England and Wales since 1995.
• Property type (detached, semi-detached, terraced, flat), whether it was a new build, and freehold or leasehold.
• Published as open data under the Open Government Licence, queryable through the Land Registry SPARQL and REST endpoints.

What it does not contain

• Floor area. You have to bring that from the EPC register yourself — which is exactly why £/sq ft is not on the portals.
• Condition. A £310,000 sale could be a gut-renovation or a finished house.
• Scotland and Northern Ireland. Scotland's data comes from Registers of Scotland, Northern Ireland's from Land and Property Services.
• Unregistered and excluded transfers. Some transfers — including certain transfers not for value — are not in the standard price paid dataset.
• What was included in the price. Fixtures, fittings and separately negotiated items are not itemised.

Reading a trend without inventing one

1. Group sales by property type before comparing anything. Mixing flats and houses produces a meaningless average.
2. Use medians on small samples.
3. Look at three to five years, not one, and expect small-postcode data to be noisy.
4. Cross-check direction against the UK House Price Index for the local authority, which is mix-adjusted and far more stable than a handful of postcode sales.

Using it in a negotiation

The strongest uses are specific: the subject property's own last sale price and date; the closest genuinely comparable sale; and the postcode median £/sq ft. The weakest use is "prices round here average X", which invites the agent to produce a different average.

If the property last sold recently at a substantially lower price with no work done in between, ask what changed. Sometimes the answer is a genuine refurbishment. Sometimes it is a fresh coat of paint and an optimistic instruction.