How to Find Your UPRN Number

Every property in Great Britain has a Unique Property Reference Number. Here is exactly how to find it — whether you need one address or thousands.

What is a UPRN and Why Do You Need One?

A UPRN (Unique Property Reference Number) is a unique numerical identifier assigned to every addressable property and land parcel in Great Britain. There are over 40 million UPRNs, covering everything from houses and flats to commercial buildings, schools, and individual units within larger developments.

UPRNs matter because they eliminate the ambiguity of address matching. "12 High Street" and "12 High St" and "12 High Street, London" all refer to the same property — but a computer cannot reliably know that without a shared reference number. UPRNs solve this problem permanently.

They are increasingly required in local government data submissions, financial services compliance workflows, and property industry applications — making the ability to find and match UPRNs an essential data capability.

Way to Find a UPRN

A UPRN (Unique Property Reference Number) is a unique numerical identifier assigned to every addressable property and land parcel in Great Britain. There are over 40 million UPRNs, covering everything from houses and flats to commercial buildings, schools, and individual units within larger developments.

When you need to find UPRNs for hundreds or thousands of addresses — particularly if those addresses are messy, incomplete, or inconsistently formatted — bulk UPRN matching is the only practical approach.

Semilariti processes your entire address list in a single upload, matching each record to its UPRN using ML algorithms that handle typos, abbreviations, and non-standard formatting automatically. Results are returned in 5 to 30 minutes with confidence scores on every match.

How Bulk UPRN Matching Works with Semilariti

Finding UPRNs for large address datasets is a three-step process:

Upload Your CSV

Prepare your address list as a CSV file — any format, any level of cleanliness. Semilariti handles non-standard formatting, missing fields, and typos.

ML Matching

Our algorithms parse, standardise, and match each address against authoritative databases. Typos are corrected, abbreviations are expanded, and each address is resolved to its UPRN.

Download Results

Receive a clean output CSV with the matched UPRN, standardised address, and confidence score alongside each original record.

Your Input

hose 7 freen line london e2 8aa

23 elmgrove london sr15 5oo

flat 4, grn st manchstr m1 2ab

Semilariti Output

House 7 Green Lane, London E2 8AA

UPRN: 5487621 · 98%

23 Elm Grove, London SE15 5PU

UPRN: 199356 · 91%

Flat 4, Green Street, Manchester M1 2AB

UPRN: 7723410 · 87%

Who Needs to Find UPRNs?

Local Authorities

Councils need UPRNs to align data across housing, revenues, planning, and social care systems. UPRN matching ensures all departments are working from the same property reference.

Banks & Mortgage Lenders

Lenders use UPRNs to identify properties unambiguously in mortgage applications, valuations, and portfolio management — reducing errors and speeding up processing.

Insurance Providers

Insurers match policy addresses to UPRNs to ensure accurate property location data feeds into underwriting models and risk assessments.

Mortgage Brokers

Brokers use bulk UPRN matching to clean and standardise client address data before submission — reducing rejections caused by address mismatches.


What a UPRN Actually Looks Like

A UPRN is a number. It is between 1 and 12 digits long, with no letters or spaces. Most UPRNs in active use are between 6 and 12 digits. An example UPRN might look like 5487621 or 200003497742. The number itself does not encode any information about the property. You cannot determine a property's location, type, or ownership from the UPRN alone. The value is that this number links to a full property record in AddressBase, which does contain all of that information — the standardised address, coordinates, property classification, and local authority area. When you receive UPRN-matched results from Semilariti, each record includes the UPRN alongside the standardised address, coordinates, and confidence score. You have both the identifier and the associated property information in a single output.

Why Different UPRN Finders Sometimes Return Different Results

If you search for the same address using different UPRN lookup tools, you may occasionally get different results. This is not always an error. Some tools match against older versions of AddressBase, which may not reflect recent property changes — new developments, sub-divisions, demolitions, or address changes. The most reliable results come from tools that match against a current or recently updated version of the dataset. Some tools use simpler matching logic that requires the input address to be clean and correctly formatted. If the address has any inconsistency, these tools may fail to find a match even when one exists. Semilariti's ML approach handles formatting inconsistencies and still finds the correct match in most cases. Some free online tools only cover a subset of the full AddressBase dataset — typically residential properties — and may not return results for commercial buildings, educational premises, or land parcels. For professional use where accuracy matters, a purpose-built bulk matching service gives more reliable results than a general-purpose online UPRN finder.

How to Interpret Confidence Scores

When you receive UPRN-matched data back from Semilariti, each record includes a confidence score. This is a measure of how certain the matching engine is that the UPRN returned is the correct one for the input address. High-confidence matches — typically above 90% — can be used directly without manual checking. The address has been clearly resolved to a single property and the match is reliable. Lower-confidence matches warrant a review. These typically occur when the input address is significantly incomplete or ambiguous — for example, a house name with no postcode in an area where several properties share a similar name. The UPRN returned may be correct, but you should verify it before updating your records. Records that could not be matched at all are returned in the output file and flagged as unmatched. These need to be investigated separately. The address may need to be obtained directly from the customer or property owner before a UPRN can be assigned.

Need to Find UPRNs at Scale?

Upload your address list and get UPRN-matched results in minutes

How to Find Your UPRN Number | UPRN Finder UK | Semilariti | Semilariti | Semilariti