UPRN
Starting question: which addressable location matches the row?
The match depends on an AddressBase relationship and may be absent.
ENGLAND AND WALES / PRICE PAID DATA / 28 AUG 2026
One sale, two keys
From 28 August 2026, HM Land Registry publishes two lookup tables alongside Price Paid Data: one for UPRN and one for INSPIRE ID. They can carry a transaction into other public datasets, but they do not rewrite history or prove who owns a place.
What you get: see what each key identifies and where a safe join stops.
Next: the same fictional transaction, run through a current release and a historical row.
HM Land Registry · official release
England and Wales · July 2026
separate lookup tables
The decisive source is the HM Land Registry release, with its technical specifications. The row in the drawing is fictional.
one starting key
1
transaction unique identifier
two tables
2
UPRN and INSPIRE ID
the useful limit
41
INSPIRE rows / one transaction, in July's file
DEMONSTRATION ROWNOT A REAL RECORD
transaction_unique_identifier
TX-DEMO-2026-07
The IDs in this diagram are example labels, not official UPRNs or INSPIRE IDs.
First-screen boundary — a key joins data rows. It does not prove an owner, an occupant, or a property's legal boundary.
The answer in two lines
The key is a bridge, not a destination.
Price Paid Data has a transaction unique identifier. The new tables repeat it in their first column and add, separately, a UPRN or an INSPIRE ID. That makes a match between datasets possible without pretending that they share one definition.
01sale row
transaction unique identifier02lookup table
transaction key + identifier03another public set
the question it can answerIn the release, the tables sit alongside Price Paid Data; do not treat them as a new column added automatically to every old file.
Two keys, two questions
UPRN and INSPIRE ID do different jobs.
A UPRN identifies an addressable location. An INSPIRE ID refers to a polygon for a registered freehold property and shows its indicative position and extent. Both can be useful, but they are not synonyms.
INSPIRE ID
Starting question: which indicative polygon is linked to the transaction?
It covers registered freehold property; leasehold and other tenures may be absent.
Where the promise stops
The new bridge is not a universal backfill.
HM Land Registry describes the lookup tables as part of the current monthly release. Its downloads page separates current files from the Price Paid history and does not promise here that every previously published row will receive the same keys retroactively.
CURRENT RELEASEa match may exist
Check the lookup file for the published month and keep the eligibility condition visible.
HISTORICAL ROWdo not assume the key
Do not turn the absence of a backfill file into a claim about every record.
The careful wording is “not promised in this package”, not “can never be found”.
When one key fans out
One transaction can have several INSPIRE IDs.
The July INSPIRE file has 82,493 rows for 77,051 distinct transaction keys. Local grouping finds at most 41 INSPIRE rows for one key. The diagram below uses only two invented labels.
TX-DEMO-2026-071 transaction key
EXAMPLE-INSPIRE-Aindicative polygonEXAMPLE-INSPIRE-Bindicative polygon
“Several” is a lookup-table behavior, not proof that the transaction is wrong or that it contains several homes.
What the bridge enables
A good key makes a question more precise.
A UPRN can be used as a parameter in a Planning Data query. That opens a research route: sale row → location → public data about that place. Each step still needs the next dataset's coverage and definition beside it.
1
Match
Join the transaction key to the right lookup.
2
Ask
Use UPRN where the downstream documentation accepts it.
3
Check
Record coverage, missing values, and the result's definition.
What not to read into a key
An identifier is not a legal verdict.
A UPRN is not proof of ownership or occupancy. An INSPIRE ID shows a polygon with indicative position and extent; do not turn it into a definitive cadastral boundary. Neither key says who lives there.
YES
You can say
“This row has a lookup key in the public file and can be tested against the next dataset's definition.”
NO
You cannot say
“The key proves the owner, occupant, legal boundary, or the existence of every dataset about the place.”
This project shows no addresses, prices, coordinates, polygons, or real identifiers.
A verification recipe
Three columns tell you whether the bridge holds.
Before publishing a join, keep the transaction key, identifier, and interpretation limit in the same note. The local audit below counts only lookup files, not all July sales.
| File | Rows | What was counted |
|---|---|---|
| UPRN | 94,112 | 94,112 distinct transaction keys |
| INSPIRE ID | 82,493 | 77,051 distinct keys; maximum 41 rows / key |
| Shared keys | 74,000 | distinct keys present in both files |
| INSPIRE fan-out | 4,466 | shared keys with multiple INSPIRE IDs |
Method: count rows in the two archived official CSVs, deduplicate their first columns, then group INSPIRE rows by transaction key. SHA-256 fingerprints are recorded in sources/SHA256SUMS.
Primary sources
- HM Land Registry release — why the tables exist.
- UPRN dataset and UPRN specification.
- INSPIRE ID dataset and INSPIRE specification.
- Price Paid Data downloads and Planning Data documentation.
Next check: when HM Land Registry changes the schema, release boundary, or licence terms; no later than 28 November 2026.