Cashback portals advertise a healthy rate at one retailer and a token rate at another, and the gap is far wider than any difference in the shopping experience. The rate is passed through from the merchant, so it tracks the merchant's margin rather than the portal's willingness to share.
The portal is paid before the shopper is
A portal is an affiliate. When a shopper clicks through, a tracking parameter is attached, and if a purchase follows within a set window the merchant pays the portal a commission on the order value.
The portal keeps part of that commission and returns the rest to the shopper as cashback. Nothing in the chain is funded by the portal itself.
So the ceiling on any advertised rate is whatever the merchant has agreed to pay. A portal can be generous only up to the point where it stops covering its own costs.
Margin sets what a merchant can afford
Commissions come out of gross margin. A category with thin margins cannot fund a large affiliate payment without the sale becoming unprofitable.
Consumer electronics is the clearest example. Hardware is sold at low margin and the retailer's return comes from attached accessories, services and finance, so the commission offered on the hardware itself is small.
Apparel, beauty and home goods carry much wider margins, which is why the same portal can offer several times the rate at a clothing site as at an electronics one.
Rates move with the retail calendar
Commission rates are not fixed contract terms so much as levers a merchant adjusts through the year. They rise when a retailer wants volume and fall when demand arrives on its own.
That produces elevated rates in the weeks before major sale events and during clearance periods, and reduced rates at peak, when the traffic would have come anyway.
The portal advertises whatever is current, which is why a rate seen last month may not be the one that applies today.
Exclusions carve out the thin categories
Most merchant programmes exclude specific categories from earning at all. Gift cards, tobacco, prescriptions, groceries and third-party marketplace items are common exclusions.
Each of these is either near-zero margin or a route to gaming the system, most obviously gift cards, which could otherwise be bought for cashback and then spent on anything.
Exclusions are the reason a large basket sometimes earns almost nothing. The order qualified, but most of what was in it did not.
Why payment takes weeks to clear
Cashback is confirmed only after the merchant confirms the sale to the affiliate network, and the merchant waits until the return window has closed.
A returned item means a reversed commission, so paying out immediately would mean chasing shoppers for money back. The delay is a clearing period, not an administrative failure.
Payment then follows the network's own settlement cycle, which adds further weeks. The sequence explains why cashback appears as pending long before it becomes spendable.