Fix: service calendars with no days switched on

Published: 3 July 2026. Last reviewed: 3 July 2026.

Code: service_has_no_active_day_of_the_week (MobilityData validator)

What this means

A row in calendar.txt has monday through sunday all set to 0, so the service runs on no day of the week. Any trip tied to that calendar never runs. It is usually a calendar that was being edited and left empty, or one whose days were cleared but the row was never deleted.

Why it matters

The trips attached to an empty calendar are invisible to riders, because they never run. That is rarely intended. Either the trips should run on some days and the calendar was left blank by mistake, or the calendar is retired and should be gone. Both cases hide the real schedule from your staff and your vendor.

How to fix it

First decide which case it is:

• The service should run: set the correct days on the calendar (switch the right monday–sunday columns to 1). Check calendar_dates.txt too, in case the days were meant to come from exception dates.
• The calendar is retired: delete the empty calendar row, and remove the trips that pointed at it if they are also retired.

In most scheduling tools this is the service or calendar editor, where you toggle the days a service pattern runs.

How long it usually takes

A few minutes once you know whether the service is meant to run. The fix itself is toggling days or deleting a row.

Authoritative rule

service_has_no_active_day_of_the_week is a canonical MobilityData GTFS Validator notice used in validator reports across the GTFS ecosystem. Read the authoritative rule for service_has_no_active_day_of_the_week in the GTFS Validator rules. (opens on an external site)