You can connect as many carrier accounts as you like, including accounts with your own negotiated rates. SKULabs shows rates from all of them on the ship screen.
To add one, go to Settings > Shipping > Carrier Accounts, click Add carrier, give the account a nickname, choose a Type, and follow the steps for that type below. For the full walkthrough, see How to set up and manage carrier accounts in SKULabs.
Direct connections (types marked "(SKULabs)")
UPS (SKULabs): enter your account number, then sign in to UPS to approve. How to connect your UPS account
FedEx (SKULabs): enter your account number on FedEx V2, then complete FedEx's address and identity verification. Setting Up FedEx V2
DHL Express (SKULabs): enter your DHL Express account details. DHL Express rates error after connecting
USPS NSA (SKULabs): USPS rates through SKULabs. What are SKULabs USPS Discounts?
Through a shipping provider
EasyPost: one API key gives you USPS plus any carriers you add in EasyPost (FedEx, UPS, DHL, Royal Mail, Australia Post and many more). How do I add a carrier account through EasyPost?
Shippo: types marked "(Shippo)", such as DHL Express, OnTrac and LaserShip. How to add DHL Express through Shippo
Stamps.com and Endicia: the "USPS (Stamps.com)" and "USPS (Endicia)" types.
Other connections
Canada Post: connected directly with the "Canada Post" type.
Amazon Shipping V2: ship Amazon orders with Amazon's labels. Using Amazon Shipping with SKULabs
Ship with Walmart and TikTok Shipping: buy labels through the marketplace for that marketplace's orders.
After connecting, you can choose which stores can use each account on the Carrier Accounts page. Questions? Reach us at support@skulabs.com or 1-800-243-2986.