diff --git a/app/src/main/java/org/transitclock/api/data/ApiServiceId.java b/app/src/main/java/org/transitclock/api/data/ApiServiceId.java
new file mode 100644
index 00000000..57a8136f
--- /dev/null
+++ b/app/src/main/java/org/transitclock/api/data/ApiServiceId.java
@@ -0,0 +1,25 @@
+/* (C)2023 */
+package org.transitclock.api.data;
+
+import java.util.List;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+import lombok.Data;
+
+/**
+ * A short description of a serviceId. For when outputting list of block IDs for service.
+ */
+@Data
+public class ApiServiceId {
+
+    @JsonProperty
+    private String id;
+
+    @JsonProperty
+    private List<String> blockIds;
+
+    public ApiServiceId(String serviceId, List<String> blockIds) {
+        this.id = serviceId;
+        this.blockIds = blockIds;
+    }
+}
\ No newline at end of file
diff --git a/app/src/main/java/org/transitclock/api/data/ApiServiceIdResponse.java b/app/src/main/java/org/transitclock/api/data/ApiServiceIdResponse.java
new file mode 100644
index 00000000..c225d4ec
--- /dev/null
+++ b/app/src/main/java/org/transitclock/api/data/ApiServiceIdResponse.java
@@ -0,0 +1,31 @@
+/* (C)2023 */
+package org.transitclock.api.data;
+
+import java.util.List;
+import java.util.Map;
+import java.util.stream.Collectors;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+import lombok.Data;
+
+/**
+ * For outputting simple list of unsorted service IDs with lists of sorted block IDs
+ */
+@Data
+public class ApiServiceIdResponse {
+
+    @JsonProperty
+    private List<ApiServiceId> serviceIds;
+
+    /**
+     * Creates the API unsorted version of list of IDs.
+     *
+     * @param services
+     */
+    public ApiServiceIdResponse(Map<String, List<String>> services) {
+        serviceIds = services.entrySet()
+                .stream()
+                .map(entry -> new ApiServiceId(entry.getKey(), entry.getValue()))
+                .collect(Collectors.toList());
+    }
+}
\ No newline at end of file
diff --git a/app/src/main/java/org/transitclock/api/resources/TransitimeApi.java b/app/src/main/java/org/transitclock/api/resources/TransitimeApi.java
index f7b6b3a4..fd353421 100644
--- a/app/src/main/java/org/transitclock/api/resources/TransitimeApi.java
+++ b/app/src/main/java/org/transitclock/api/resources/TransitimeApi.java
@@ -18,6 +18,7 @@
 import org.transitclock.api.data.ApiRoutesDetailsResponse;
 import org.transitclock.api.data.ApiSchedulesHorizStops;
 import org.transitclock.api.data.ApiSchedulesVertStopsResponse;
+import org.transitclock.api.data.ApiServiceIdResponse;
 import org.transitclock.api.data.ApiTrip;
 import org.transitclock.api.data.ApiTripPatternsResponse;
 import org.transitclock.api.data.ApiTripWithTravelTimes;
@@ -870,6 +871,23 @@ ResponseEntity<ApiSchedulesHorizStops> getScheduleHorizStops(
             tags = {"base data", "serviceId"})
     ResponseEntity<ApiIdsResponse> getServiceIds(StandardParameters stdParameters);
 
+    /**
+     * Handles the "serviceIds" command. Returns list of all service IDs with assigned blocks.
+     *
+     * @param stdParameters
+     *
+     * @return
+     *
+     * @
+     */
+    @GetMapping(value = "/command/serviceIdsWithBlocks",
+            produces = {MediaType.APPLICATION_JSON_VALUE, MediaType.APPLICATION_XML_VALUE})
+    @Operation(
+            summary = "Retrives all service id with block ids.",
+            description = "Retrives all service id with block ids.",
+            tags = {"base data", "serviceId"})
+    ResponseEntity<ApiServiceIdResponse> getServiceIdsWithBlocks(StandardParameters stdParameters);
+
     /**
      * Handles the currentServiceIds command. Returns list of service IDs that are currently active.
      *
diff --git a/app/src/main/java/org/transitclock/api/resources/TransitimeResource.java b/app/src/main/java/org/transitclock/api/resources/TransitimeResource.java
index ca2587a8..4f00e88a 100644
--- a/app/src/main/java/org/transitclock/api/resources/TransitimeResource.java
+++ b/app/src/main/java/org/transitclock/api/resources/TransitimeResource.java
@@ -24,6 +24,7 @@
 import org.transitclock.api.data.ApiRoutesResponse;
 import org.transitclock.api.data.ApiSchedulesHorizStops;
 import org.transitclock.api.data.ApiSchedulesVertStopsResponse;
+import org.transitclock.api.data.ApiServiceIdResponse;
 import org.transitclock.api.data.ApiTrip;
 import org.transitclock.api.data.ApiTripPatternsResponse;
 import org.transitclock.api.data.ApiTripWithTravelTimes;
@@ -866,6 +867,20 @@ public ResponseEntity<ApiIdsResponse> getServiceIds(StandardParameters stdParame
         }
     }
 
+    @Override
+    public ResponseEntity<ApiServiceIdResponse> getServiceIdsWithBlocks(StandardParameters stdParameters) {
+        try {
+            // Get Vehicle data from server
+            Map<String, List<String>> idsWithBlockIds = configService.getServiceIdsWithBlockIds();
+
+            ApiServiceIdResponse apiServiceIds = new ApiServiceIdResponse(idsWithBlockIds);
+            return stdParameters.createResponse(apiServiceIds);
+        } catch (Exception e) {
+            // If problem getting data then return a Bad Request
+            throw WebUtils.badRequestException(e);
+        }
+    }
+
     @Override
     public ResponseEntity<ApiIdsResponse> getCurrentServiceIds(StandardParameters stdParameters) {
         try {
diff --git a/libs/core/src/main/java/org/transitclock/gtfs/DbConfig.java b/libs/core/src/main/java/org/transitclock/gtfs/DbConfig.java
index 1ae5d4d4..d721b35c 100644
--- a/libs/core/src/main/java/org/transitclock/gtfs/DbConfig.java
+++ b/libs/core/src/main/java/org/transitclock/gtfs/DbConfig.java
@@ -684,6 +684,23 @@ public int getBlockCount() {
         return blockCount;
     }
 
+    /**
+     * Returns sorted lists of block IDs what belong to all service IDs
+     *
+     * @return Map of all service IDs with belong to block IDs
+     */
+    public Map<String, List<String>> getBlockIdsForAllServiceIds() {
+        Map<String, List<String>> serviceIdsWithBlocks = new HashMap<>();
+
+        blocksByServiceMap.forEach((key, element) -> {
+            List<String> ids = new ArrayList<>();
+            element.forEach((innerKey, block) -> ids.add(block.getId()));
+            Collections.sort(ids);
+            serviceIdsWithBlocks.put(key, ids);
+        });
+        return serviceIdsWithBlocks;
+    }
+
     /**
      * Returns blocks for the specified blockId for all service IDs.
      *
diff --git a/libs/core/src/main/java/org/transitclock/service/ConfigServiceImpl.java b/libs/core/src/main/java/org/transitclock/service/ConfigServiceImpl.java
index f33dad3e..d2edc83f 100644
--- a/libs/core/src/main/java/org/transitclock/service/ConfigServiceImpl.java
+++ b/libs/core/src/main/java/org/transitclock/service/ConfigServiceImpl.java
@@ -4,6 +4,7 @@
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.List;
+import java.util.Map;
 import java.util.stream.Collectors;
 
 import org.transitclock.core.dataCache.PredictionDataCache;
@@ -389,4 +390,12 @@ public List<IpcRoute> getRoutesByStopId(String stopId) {
                                              null))
                 .collect(Collectors.toList());
     }
-}
\ No newline at end of file
+  
+    /* (non-Javadoc)
+     * @see org.transitclock.ipc.interfaces.ConfigInterface#getServiceIdsWithBlockIds()
+     */
+    @Override
+    public Map<String, List<String>> getServiceIdsWithBlockIds() {
+        return dbConfig.getBlockIdsForAllServiceIds();
+    }
+}
diff --git a/libs/core/src/main/java/org/transitclock/service/contract/ConfigService.java b/libs/core/src/main/java/org/transitclock/service/contract/ConfigService.java
index 68dad043..e3a928e7 100644
--- a/libs/core/src/main/java/org/transitclock/service/contract/ConfigService.java
+++ b/libs/core/src/main/java/org/transitclock/service/contract/ConfigService.java
@@ -14,6 +14,7 @@
 
 import java.util.Collection;
 import java.util.List;
+import java.util.Map;
 
 /**
  * Defines the RMI interface for getting configuration data.
@@ -52,7 +53,7 @@ IpcRoute getRoute(String routeIdOrShortName, String directionId, String stopId,
     /**
      * Obtains ordered list of route details
      *
-     * @param routeIdOrShortName
+     * @param routeIdsOrShortNames
      * @return
      */
     List<IpcRoute> getRoutes(List<String> routeIdsOrShortNames);
@@ -184,4 +185,12 @@ IpcRoute getRoute(String routeIdOrShortName, String directionId, String stopId,
      * @return list of IpcRoute
      */
     List<IpcRoute> getRoutesByStopId(String stopId);
+  
+  
+    /**
+     * Returns sorted lists of block IDs what belong to all service IDs
+     *
+     * @return Map of service IDs with belong block IDs
+     */
+    Map<String, List<String>> getServiceIdsWithBlockIds();
 }