Amazon's SFP requirements force fast delivery on every Prime order — but the carrier strategy was UPS Ground for everything. For sub-1lb orders that don't need 2-day, that's a ~$3 overpay per order. At 5,400 Amazon orders / month, that's ~$16K of avoidable spend monthly.
We built a per-order routing logic that splits the SFP volume between USPS Priority (sub-1lb, regional) and UPS Ground (heavier or distant). Both qualify for Prime if delivered inside the SLA. The brand saw zero impact on Prime eligibility metrics — Amazon's dashboards never moved.
Shipping dropped from 18% to 12% of revenue across the next two quarters. At their gross margin, that's six points of contribution margin — millions in run-rate. We also caught back $11K in late-delivery refunds during the transition that were never claimed.
“Shipping was eating 18% of our revenue. For an Amazon SFP seller, that's the line between growing and standing still. Kadima got us to 12% without changing a single carrier. Six points of margin, straight back to us.