Changelog
17/06/2026 · TGSS: empty results, 404

TGSS: empty results, 404 instead of 502

17/06/2026

Until today, when Sistema RED answered a query saying that there is nothing, the API returned it as 502, the same as an authority failure. For example:

  • SISTEMA RED: Error: 3543* NO EXISTEN DATOS PARA ESTA CONSULTA
  • SISTEMA RED: No hay registros para el movimiento seleccionado!
  • SISTEMA RED: No se encontró el informe con la fecha solicitada.
  • SISTEMA RED: No existe información para el período solicitado.
  • SISTEMA RED: Error. El Empleado no está en situación de Alta. Consulte Situación de Empleado en la Empresa

For an integration that is indistinguishable from an outage, so the reasonable response was to retry — and retrying a query with no results always returns the same.

From now on:

CodeWhen
404TGSS answered and there is no data for that query. Final answer: do not retry.
502TGSS rejects the operation for another reason, or answers unexpectedly.

The response body does not change: same success, message and errors.tgss with the authority's text. Only the HTTP status changes.

It affects TGSS queries, reports and duplicates, among others: Employee status, CCC status, IDC, Affiliate work history, TA document duplicates, FIE files, Maternity/paternity duplicate, Check IT, Collective agreements query and A1 form.

What to check in your integration: if you treat any 5xx as "retry", 404 now leaves that path and you stop repeating queries that will not change.