Orders are not the unit on every shipping charge
Two fulfillment proposals can cover the same number of customer orders and still produce different parcel counts. If one proposal splits baskets into two shipments, a per-parcel seasonal adjustment appears twice. Compare the resulting shipment file before comparing an average cost per order.
USPS announced its 2026 temporary holiday price change on August 25 and subsequently confirmed implementation on October 4. The stated window ends at 12 a.m. Central on January 17, 2027. This is a temporary price adjustment, not a fuel surcharge. Announcement; implementation confirmation.
Isolate one part of the bill
For commercial domestic USPS Ground Advantage in zones 1–4, the published increase is $0.40 for the 0–3 lb weight band and $0.65 for 4–10 lb. The schedule also specifies cubic tiers; our example assumes weight-based rating and excludes cubic and oversized parcels. USPS schedule.
Consider 100 illustrative orders with two possible packing plans. The weights below are assumed rated weights, including packaging; they are not measured products or a carrier quote.
| Plan | Parcels | Assumed rated weight | Seasonal increment per parcel | Increment total |
|---|---|---|---|---|
| Two parcels per order | 200 | 2 lb each | $0.40 | $80 |
| One parcel per order | 100 | 5 lb each | $0.65 | $65 |
The second plan has $15 less in this seasonal component: $80 minus $65. That is $0.15 per customer order. It does not establish a $15 reduction in the full shipping bill. The base rate, box, packing labor and other applicable charges have not been calculated.
Require a second comparison before choosing
Ask each 3PL for an order-level export with parcel count, service, zone, rated weight and the price basis used. Keep the carrier adjustment separate from warehouse pick fees and packaging. If the provider bundles transportation charges, request an explanation of how the seasonal change affects the bundled price.
Do not assume the published USPS increase passes through unchanged. Your agreement may use negotiated rates or a different billing arrangement. Record that treatment as unknown until the provider supplies the applicable terms. A public carrier table cannot resolve a private fulfillment contract.
Turn the example into a quote check
Select a small set of your actual baskets and ask both candidates to describe the packing plan. Compare the complete price for the same service assumptions, then repeat for plausible split shipments. Retain the seasonal line as one component of that comparison.
The useful conclusion is narrower than “one box is cheaper.” Parcel count changes exposure to parcel-level charges, while weight and dimensions can change the rate category. A good quote explains both. Recheck the official schedule and your contract before applying these figures to a shipment date.
Related reading
Sources
- https://about.usps.com/newsroom/national-releases/2026/0825-usps-announces-temporary-price-change-for-2026-holiday-shipping-season.htm — accessed 2026-10-16
- https://news.usps.com/daily/2026/10/05/ — accessed 2026-10-16