Checkout shows shipping rates, but the endpoint says “Country/region not supported”?
A September 7, 2026 Shopify Developer Community report reproduced this mismatch in a Market-driven shipping preview shop when selecting a country without provinces. That is a specific preview/runtime symptom, not proof that your app’s migration logic is wrong.
THE OBSERVED MISMATCH
Same address, different result paths.
- Storefront checkout displayed shipping rates for the address.
- Legacy shipping-rate endpoints returned “Country/region not supported” for the same market context.
- The follow-up report specifically mentioned a country without provinces.
- The report came after an earlier preview-shop data issue in the same thread had already been fixed by Shopify.
That combination makes it important to isolate the failing endpoint, market context and address shape before changing production migration code.
REPRODUCTION CHECKLIST
Capture enough evidence to separate app logic from preview behavior.
- Reproduce with a fresh development store using the current Market-driven shipping feature preview.
- Record country, province/subdivision availability, postal code and the market selected by Shopify.
- Compare the shipping rates visible at checkout with the exact endpoint response consumed by your app.
- Capture request IDs and timestamps for failing API calls.
- Repeat with a country that has provinces/states and one that does not.
- Confirm whether your app is reading merchant-owned shipping configuration through deprecated delivery-profile paths.
- Do not classify the issue as a migration regression until the platform-preview path and your app path have been separated.
MIGRATION CONTEXT
Market-driven shipping changes the source of truth.
Shopify is moving merchant-owned shipping configuration from delivery profiles into Markets. For shops on Market-driven shipping, merchant-owned delivery-profile reads can represent a stale legacy snapshot, while supported market shipping configuration is exposed through Markets.
If the failing endpoint sits next to merchant-owned delivery-profile assumptions, treat the preview symptom and the migration dependency as two separate debugging tracks.
SHIPREADY
Check whether your app actually sits on the migration path.
The free checker identifies merchant-owned read/write exposure, app-owned profile separation, feature-preview testing status and compatibility-confirmation pressure.
SOURCES
Shopify Developer Community: endpoint failures and country/region follow-up ↗
Shopify: Upgrade your app for Market-driven shipping ↗
Shopify: merchant-owned delivery profile API deprecation ↗
Community reports describe specific environments. Reproduce the issue and verify current Shopify documentation before changing production code.