Squawk Codes

The Squawk Codes page is a searchable reference table (currently 6,800+ entries) decoding UK transponder squawk codes — the four-digit code an aircraft’s transponder transmits, assigned by ATC or used for a specific purpose.

Columns

• Code — the four-digit squawk code.
• Description — what the code means or is assigned to (a specific unit, purpose, or monitoring service).
• Frequency — the associated frequency where relevant, or “ATC in Vicinity” where the code isn’t tied to one specific frequency.

Using the Table

Use the Filter box to search across all columns — handy if you’ve spotted a squawk code on the map (see Reading the Aircraft Info Panel in the Live Traffic category) and want to know what it means, or if you’re looking up a specific unit or service. Click any column header to sort, and use the Show entries dropdown to control how many rows are shown per page.