Kearney published a piece in Supply Chain Xchange this summer arguing that the parcel market has split into a barbell. Ultra-fast delivery at a premium on one end, deliberately slow delivery at low cost on the other, and shippers should pick an end based on what their customers actually want rather than assuming everyone wants speed.

The framing is right, and the piece contains the best sentence written on this subject in a while: “Customers can live with slow. They won’t forgive unreliable.”

What it does not do is cost either end. It treats the slow side as self-evidently the cheap side, which is how almost everyone treats it. That assumption does not survive contact with the carriers’ 2026 rate tables.

Slowing down moves the base rate, not the stack

Move a package from a two-day service to a five-day service and you change what you pay for transit. You do not change the residential delivery charge, the delivery area surcharge, additional handling, or peak. Those are priced on where the package is going and what it looks like, not on how fast it travels.

Transit is also the component that has grown slowest. The accessorial stack is where the growth has been, which is the same reason a FedEx bill climbs when the rates do not. The slow strategy discounts the line that was already the least of your problems.

The rail the slow strategy runs on was repriced all year

The slow end in the United States runs heavily on USPS Ground Advantage, and Ground Advantage commercial moved three times on the base rate this year: 7.8% in January, 8% as a temporary increase in April, and 11.8% in July. Peak pricing lands on top of all of it from October 4, at roughly 40% above last year’s peak. I broke those down when the July increase published.

A shipper who moved to the slow end in January and left it there has absorbed every one of them.

The July change is the one that does not look like a price increase, and it is the one that matters most here. Cutting the dimensional divisor from 166 to 139 raises the billable weight of the same box without touching the published rate. If your product is light and bulky, which describes a great deal of what ships slow, that landed harder than the headline percentage did.

Adopting the slow end changes your shipping profile. Your baseline does not move

This is the part a strategy piece cannot see, because it is not in customer research. It is in two published rate tables.

Start with what actually saves money at the slow end. Most of it is the service downgrade itself: two-day to ground, Priority to Ground Advantage. You get that by changing what you buy, not how you operate. The rest comes from consolidation, holding orders and releasing them in fewer, larger drops.

That second part is where the interaction lives, and it is narrower than it looks.

Consolidating inside a week does nothing to your peak exposure. Move from daily releases to Monday, Wednesday and Friday and your weekly total is unchanged. Both carriers measure the week, not the day.

What moves the number is a change in cadence across weeks, and only if you made it after June.

FedEx and UPS both measure your average weekly volume across a four-week window in June, both engage above 20,000 packages in a week, each counting a different package mix, and both begin charging at 105% of that baseline. I set the two schedules against each other in a separate piece.

If you were already running your slow cadence in June, the baseline absorbed it and nothing shifts. If you adopted it in July or August, your peak weeks are lumpier than the June that measured you, and the surcharge is calculated on that gap.

UPS published a worked example. At 175% of baseline the charge is $2.65, applied to every package that week rather than only the ones above the line. Against a 20,000 baseline, a 35,000 package week costs $92,750. The same volume released evenly sits at 100% and costs nothing.

Same annual volume, same customers, same delivery promise. The variable is when you changed how you ship relative to a window that closed in June.

None of that argues against consolidating, which remains the right way to run a slow network. It argues that the saving and the surcharge are calculated on the same underlying number, and most cost models for a slow strategy contain only one of them.

Two UPS provisions close the escape route a reader would reach for next, and both are worth knowing before you commit. Both are covered in full in that piece.

You may not be able to opt out. UPS qualification looks back to any week after October 2025 and holds until further notice, so one outsized week last peak puts you on that schedule now. Running lighter this year does not remove you from it.

And the slow strategy can walk you into the second one. UPS reopens its baseline between August 30 and September 26, and a shipper who moved volume off UPS during the year is likely to be running lighter in exactly that window. That is the condition that trips it, and the reset works against you rather than for you.

So the slow strategy can qualify you on volume you shipped last year, and then reprice you on volume you moved away this year. Neither of those shows up in a customer survey.

Cheap and slow, and slow with date certainty, are two different products

The article is right that a slow shipper still owes the customer accuracy, and it lists what that requires: near-real-time tracking, dynamic estimated arrival, day-definite delivery, delivery status notification.

Now price those.

In the US parcel market, the services that are cheapest at the slow end are generally the ones with the least date certainty and the coarsest tracking. Day-definite is often a paid feature or a different service level, not a property of slow shipping. So the article’s two requirements pull against each other in the market as it actually exists. You can buy cheap and slow. You can buy slow with date certainty. The second costs more than the first, and the difference is not small.

That gap between what an alternative service costs and what it reliably delivers is the one I priced in the trust gap piece, and it is where slow strategies most often fail. Not because the parcels arrive late, but because nobody priced the certainty.

What the barbell decision actually needs

None of this argues for the fast end. The barbell is real, and for many shippers the slow end is the correct choice.

It argues that the decision has two halves and the article supplies one. The customer half asks what your buyers will tolerate, and Kearney answers it well. The cost half asks what each end costs to run against carrier schedules that do not price on speed. You can get the first half exactly right and still lose money, because the second half is where the money moves.

The practical version: model the accessorial stack rather than the transit rate, model your peak weeks against a June baseline you have already shipped, and price date certainty as its own line rather than assuming it comes free.

Takeaway: Slower is a service decision. Cheaper is a rate table decision. They are not the same decision.

Which half of that does your model actually cover?