Discounts off base transportation can be substantial for volume shippers; the discount band on protected surcharges (residential, DAS, peak) is much narrower or zero. The gap between list and negotiated on base alone is often the single largest available saving.
Not a charge — an entitlement most small shippers never claim. When an account is linked and rates are requested correctly, carriers return discounted negotiated rates instead of list. Many SMBs ship at list rate without knowing the discount is sitting there.
Carriers return two kinds of rates through their systems: published list rates, and negotiated rates tied to a linked account. When a shipper's account is linked to their integration and the rate request is structured to ask for negotiated rates (for UPS, by including the account and billing details so the response carries the negotiated charges), the carrier returns the discounted figures. Many small shippers — especially those routing through aggregators or shipping at retail counters — never link their account correctly and pay list rate on shipments that should price lower.
This is the entry the rest of the Atlas depends on, because a 'fair' benchmark is meaningless without negotiated rates. It is also the clearest illustration of the asymmetry ShipFair exists to close: the discount is available, published, and waiting; the barrier is purely knowing how to claim it. ShipFair's open-source carrier integration exists precisely so that linking an account and requesting negotiated rates is no longer the hard part.
UPS negotiated rates are returned via the Rating API when the account number and billing details are included in the request (see UPS Rating API documentation and the ShipFair open-source UPS integration).