diff --git a/src/main/java/org/mtransit/parser/DefaultAgencyTools.java b/src/main/java/org/mtransit/parser/DefaultAgencyTools.java
index 4c491135..ae78bac5 100644
--- a/src/main/java/org/mtransit/parser/DefaultAgencyTools.java
+++ b/src/main/java/org/mtransit/parser/DefaultAgencyTools.java
@@ -356,11 +356,30 @@ public boolean excludeAgencyNullable(@Nullable GAgency gAgency) {
 
 	@Override
 	public boolean excludeAgency(@NotNull GAgency gAgency) {
+		final org.mtransit.parser.config.gtfs.data.AgencyConfig agencyConfig = Configs.getAgencyConfig();
+		if (agencyConfig == null) {
+			return KEEP;
+		}
+		final String agencyId = agencyConfig.getAgencyId();
+		final List<String> otherAgencyIds = agencyConfig.getOtherAgencyIds();
+		final boolean hasAgencyId = agencyId != null;
+		final boolean hasOtherAgencyIds = !otherAgencyIds.isEmpty();
+		if (!hasAgencyId && !hasOtherAgencyIds) {
+			return KEEP; // no filters
+		}
 		//noinspection DiscouragedApi
-		if (getAgencyId() != null && gAgency.isDifferentAgency(getAgencyId())) {
-			return EXCLUDE;
+		if (hasAgencyId && !gAgency.isDifferentAgency(agencyId)) {
+			return KEEP;
 		}
-		return KEEP;
+		if (hasOtherAgencyIds) {
+			for (final String otherAgencyId : otherAgencyIds) {
+				//noinspection DiscouragedApi
+				if (!gAgency.isDifferentAgency(otherAgencyId)) {
+					return KEEP;
+				}
+			}
+		}
+		return EXCLUDE;
 	}
 
 	private final Map<String, String> serviceIdToCleanupServiceId = new HashMap<>();
diff --git a/src/main/java/org/mtransit/parser/config/gtfs/data/AgencyConfig.kt b/src/main/java/org/mtransit/parser/config/gtfs/data/AgencyConfig.kt
index 5ff10ec9..d0e62fd2 100644
--- a/src/main/java/org/mtransit/parser/config/gtfs/data/AgencyConfig.kt
+++ b/src/main/java/org/mtransit/parser/config/gtfs/data/AgencyConfig.kt
@@ -10,6 +10,11 @@ data class AgencyConfig(
      */
     @SerialName("agency_id")
     val agencyId: String? = null, // OPT-IN filter
+    /**
+     * (Optional) Agency IDs filter (useful when multiple agencies in same GTFS)
+     */
+    @SerialName("other_agency_ids")
+    val otherAgencyIds: List<String> = emptyList(), // OPT-IN filter
     /**
      * Route type filter (integer from GTFS Static `routes.txt` > `route_type` field)
      * (useful when multiple route type in same GTFS)