Bulk Postcode Lookup

This tool lets you look up location data for multiple UK postcodes in a single request. Paste up to 50 postcodes and get the town, county, region, latitude and longitude for each one. Results can be exported as a CSV file or copied to your clipboard for pasting into a spreadsheet.

How to Use It

Paste your postcodes into the text box, one per line or separated by commas. The tool accepts any standard UK postcode format with or without spaces. Duplicates are removed automatically. Hit "Look Up All" and the results appear in a table below. Any postcodes that could not be found are flagged so you can check them.

Input Formats

The tool handles several input formats. You can paste one postcode per line, which is the cleanest approach. You can also use comma-separated values on one or more lines. Spaces within postcodes are optional, so both "M25 0AA" and "M250AA" work. The tool strips whitespace and normalises everything before looking it up.

Export Options

The CSV export downloads a file containing all columns: postcode, town, county, region, country, latitude and longitude. This is ready to open in Excel, Google Sheets, or import into a database. The "Copy Table" button copies the table data as tab-separated values, which pastes cleanly into spreadsheet cells.

Common Uses

Geocoding a Dataset

If you have a list of customer postcodes, delivery addresses, or survey respondents and need to add geographic coordinates, this tool gives you lat/lng values you can use for mapping, distance calculations, or spatial analysis. The coordinates are postcode centroid values using the WGS84 datum, compatible with Google Maps, Leaflet, and all major mapping platforms.

Data Enrichment

Adding town, county and region columns to a postcode list is useful for reporting, segmentation and analysis. If your dataset only has postcodes, this tool fills in the administrative geography so you can group and filter by location. The admin district corresponds to the local authority, which is the level used for most government statistics.

Address Validation

Pasting a batch of postcodes and checking for "not found" results is a quick way to identify invalid or terminated postcodes in your data. Typos, transposed characters, and old postcodes that have been retired will show up as not found. This is a simple first-pass data quality check before running more detailed validation.

Mail and Marketing

Direct mail campaigns need clean postcode data to avoid wasted postage. Running your mailing list through a bulk lookup flags any postcodes that don't match the Royal Mail database, helping you clean your list before printing. The region and county data also helps you segment campaigns geographically.

Rate Limits

This tool is capped at 50 postcodes per request. This keeps the response time fast and the server load manageable. If you need to process larger batches, split your list into groups of 50 and run them separately. For very large datasets (thousands of postcodes), consider using the Postcodes.io bulk API endpoint or the ONS Postcode Directory download, both of which are free.

Data Accuracy

The coordinates returned are the centroid of each postcode unit, accurate to within approximately 50-100 metres of any specific address within that postcode. The town and county values come from the ONS Postcode Directory and represent the local authority district and administrative county. Some postcodes span local authority boundaries, in which case the district shown is the one containing the majority of addresses in that postcode.