Y-splits (T-calls)

Some loads require more than one driver to complete the delivery. This is known as a Y-split or T-call, where a route is split into multiple segments, each assigned to a different driver. Samsara’s Routes API supports both planned and ad hoc Y-splits.

Planned Y-splits

If your TMS knows in advance that multiple drivers will move the load in segments, you can create multiple routes from the start—one for each driver—with stops representing their portion of the load.

Example flow:

1. Create Route 1 for Driver A (first leg)
2. Create Route 2 for Driver B (second leg)
3. Optionally, use notes or external IDs to correlate the two segments as part of a single load

Example request to create Route 1 (first leg):

curl -X POST 'https://api.samsara.com/fleet/routes' \
--header "Authorization: Bearer <TOKEN>" \
--header "Content-Type: application/json" \
--data '{
  "name": "Load #9876 - Leg 1",
  "driverId": "123456",
  "stops": [
    {
      "addressId": "10001",
      "scheduledDepartureTime": "2025-03-25T13:00:00Z"
    },
    {
      "addressId": "10002",
      "scheduledArrivalTime": "2025-03-25T15:00:00Z"
    }
  ]
}'

Example request to create Route 2 (second leg):

curl -X POST 'https://api.samsara.com/fleet/routes' \
--header "Authorization: Bearer <TOKEN>" \
--header "Content-Type: application/json" \
--data '{
  "name": "Load #9876 - Leg 2",
  "driverId": "654321",
  "stops": [
    {
      "addressId": "10002",
      "scheduledDepartureTime": "2025-03-25T15:30:00Z"
    },
    {
      "addressId": "10003",
      "scheduledArrivalTime": "2025-03-25T18:00:00Z"
    }
  ]
}'

In this example, both routes share the transfer point stop (addressId: 10002), with a handoff between Driver A and Driver B.

Ad-hoc Y-splits

Sometimes, Y-splits are unplanned and happen during execution (e.g., due to a breakdown, hours-of-service limit, or unexpected dispatch change). You can split a route mid-route using the following process:

Step-by-step:

1. Edit the original route using PATCH /fleet/routes/:id to remove stops no longer assigned to the original driver.
2. Create a new route using POST /fleet/routes, starting from the handoff point and assigned to the next driver.

Example: Ad hoc split at second stop

Original route (before split):

Stop 1 → Stop 2 → Stop 3
Driver A

After Y-split:

• Driver A completes Stop 1 and Stop 2.
• Driver B picks up from Stop 3.

1. Update the original route to end at Stop 2:

curl -X PATCH 'https://api.samsara.com/fleet/routes/ROUTE_ID' \
--header "Authorization: Bearer <TOKEN>" \
--header "Content-Type: application/json" \
--data '{
  "stops": [
    {
      "id": "STOP_1_ID"
    },
    {
      "id": "STOP_2_ID"
    }
  ]
}'

2. Create a new route for Driver B from Stop 3:

curl -X POST 'https://api.samsara.com/fleet/routes' \
--header "Authorization: Bearer <TOKEN>" \
--header "Content-Type: application/json" \
--data '{
  "name": "Ad hoc leg for Load #9876",
  "driverId": "654321",
  "stops": [
    {
      "addressId": "10003",
      "scheduledArrivalTime": "2025-03-25T18:00:00Z"
    }
  ]
}'