Rate Shopping and Comparison
Get Rates for a Shipment
- Collect: origin address, destination address, parcel (length, width, height, distance_unit, weight, mass_unit). All dimension and weight values must be strings (e.g.,
"10"not10). - Optionally validate both addresses with
ValidateAddress(see Address Validation). - Call
CreateShipmentwithaddress_from,address_to(as inline address objects using v1 field names --street1,city,state,zip,country-- not object IDs), andparcels. - The response
ratesarray contains available options. Present a table: carrier, service level, price, estimated days. - Note: the same carrier may return duplicate rates from multiple carrier accounts. Present the best rate per carrier/service combination.
- Each rate carries an
object_id. To buy a label, pass the chosen rate'sobject_idto the purchase flow (see Label Purchase); you do not re-send the address or parcel.
Rate Expiration
Rates expire after 7 days. If a user tries to purchase a rate that was retrieved more than 7 days ago, create a new shipment to get fresh rates.
Filter by Speed
Map user requests: "overnight" = estimated_days 1, "2-day" = estimated_days <= 2, "within N days" = estimated_days <= N. Filter the rates array accordingly. If nothing matches, show the fastest available option.
International Rates
Some carriers may return international rates without a customs declaration, but others will not. If no rates are returned, try attaching a customs declaration to the shipment. Some carriers also require a phone number on the destination address for international rate retrieval. Inform the user that customs will be required at label purchase time regardless. See shippo/references/customs-guide.md for customs details.
Checkout Rates (Line Items)
Call CreateLiveRate instead of CreateShipment. Accepts address_from, address_to, and line_items (each with title, quantity, total_price, currency, weight, weight_unit).
Rates in a Specific Currency
Call ListShipmentRatesByCurrencyCode with the preferred ISO currency code (USD, EUR, GBP, CAD, etc.).
Recommendation
Identify the cheapest (lowest amount), fastest (lowest estimated_days), and best-value options from the rates array. These are not API fields -- compute them by sorting the rates array yourself. State the trade-off: "Option A is $X cheaper but takes Y more days than Option B."
Troubleshooting: No Rates
- Verify both addresses passed validation (most common cause).
- Confirm parcel dimensions are reasonable (not zero, not exceeding carrier limits).
- Shippo provides managed carrier accounts by default for major carriers. If no rates are returned, the issue is more likely address validation, unsupported route, or parcel dimensions -- not missing carrier accounts. You can verify with
ListCarrierAccountsif needed. - Rates expire after 7 days. If stale, create a new shipment to get fresh rates.
Quick Reference
Get rates:
(optional) ValidateAddress (x2) -> CreateShipment (with inline addresses) -> read rates array


