Add the carrier to shipping zones or markets

Why this matters

Checkout only asks this app for rates where OO - Shipping Rate & Rules is added as a carrier-calculated method. Creating the carrier service alone is not enough.

From Shopify Admin API 2026-10, creating a carrier service no longer automatically adds it to the shop’s default shipping profile. The app helps attach it for you.

What the app does automatically

When you open the app (and after install), if the carrier is active and not on any zone or market yet, the app adds it for you — without removing the merchant’s other rates.

If the carrier is already on some zones but missing from others, use Add to remaining zones (or markets) on the home screen.

Legacy shipping profiles vs market-driven shipping

• Classic shops — the carrier is attached on each Shopify shipping zone under Settings → Shipping and delivery.
• Market-driven shipping shops — the carrier is attached as a carrier-calculated option on each Shopify market that owns its own shipping configuration. Markets that only inherit shipping are not overwritten.

The home copy switches between “shipping zones” and “markets” based on the shop model.

Manual check

1. Open Settings → Shipping and delivery (or Markets, on market-driven shops).
2. Confirm OO - Shipping Rate & Rules is present where you expect rates.
3. Place a test checkout to a matching destination.

Related help

• Shopify plan requirements
• Rates missing at checkout
• Market-driven shipping