When importing shipments via CSV, you must use the following format in the "postage_type" field:
usps_express*
usps_express_mail_international*
usps_first
usps_first_class_mail_international
usps_first_class_package_international_service
usps_media_mail*
usps_parcel_select*
usps_priority
usps_priority_mail_international
chit_chats_canada_tracked*
chit_chats_collect
chit_chats_select
chit_chats_slim
chit_chats_international_tracked
chit_chats_us_select
chit_chats_us_edge
If no postage type is defined:
- the postage will display as "unknown". The unknown postage type may be used together with the field cheapest_postage_type_requested to automatically select the cheapest postage rate for U.S. shipments.
Based on your shipment settings, if the postage type is defined but rates are not available:
- the import will fail with 'unable to fetch postage rate' errors
- the shipment will be imported as an “unknown” postage type. After the import, you can update any affected shipments and proceed to purchase postage. For reasons why a postage rate may be unavailable, please see our support article “Why can’t I buy postage?”
*Service availability may vary