Below is a list of carrier codes that are support in ChannelAdvisor.
Carrier Class
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USPS PRIORITY
USPS PARCELPOST
USPS MEDIA
USPS FIRSTCLASS
USPS EXPRESS
USPS GEM
USPS APP
USPS INTLPARCEL
USPS GEGDS
USPS GEGNDS
USPS GPMFLEL
USPS GPMDRES
USPS GPMVWES
USPS AMLP
USPS ESLP
USPS POSTCARD
USPS LIBRARYMAIL
USPS BOUNDPRINTEDMATTER
USPS PRESORTEDFIRST
USPS PRESORTEDSTANDARD
USPS INTLLETTER
USPS INTLAIRLETTER
USPS INTLPOSTCARD
USPS INTLAEROGRAMME
USPS INTLAIRPARCEL
USPS IECONOMY
FEDEX OVERNIGHT
FEDEX 2DAY
FEDEX GROUND
FEDEX PRIORITY
FEDEX 1STOVERNIGHT
FEDEX EXPSAVER
FEDEX OVERNIGHTFREIGHT
FEDEX 2DAYFREIGHT
FEDEX EXPSAVERFREIGHT
FEDEX INTLPRIORITY
FEDEX INTLECONOMY
FEDEX INTLFIRST
UPS NEXTDAY
UPS 2DAY
UPS GROUND
UPS WWE
UPS WWEX
UPS STD
UPS 3DS
UPS NDAS
UPS NDAEA
UPS WWEP
UPS 2DAA
UPS ES
AIRBORNE OVERNIGHT
AIRBORNE 2DAY
AIRBORNE GROUND
FREIGHT GROUND
The list of all supported shipping carriers and classes in a customer's account (including custom ones) can be found under:
Channel Management > All Sales > Import Shipping Tracking Numbers > (help link in left nav) > (link to list of shipping carriers and classes in page).