Analysis · Verified against Amazon Seller Central, 27 August 2026; re-checked 10 October 2026 against Amazon’s published fee pages (US, plus UK and Europe)
Amazon published its own before-and-after comparisons for the 15 January 2026 change. Five products, five different outcomes, ranging from a $0.74 saving to a 51% increase.
What this is. Amazon’s own published figures, collected and read together. No modelling and no estimates — these are the comparisons Amazon put in its help documentation, which most sellers never opened.
What changed on 15 January 2026, and why dimensional weight is not new, is set out in Amazon’s 2026 FBA fee changes explained.
None of these bulky-fee changes applies in the UK. There is no equivalent European size-tier change for 2026 — European referral fees were cut in several categories in December 2025 and January 2026, FBA parcel fees fell from December 2025, and some other fees, such as monthly storage, rose. Don’t transplant the American numbers onto UK SKUs. UK sellers do face a 1.5% fuel and logistics surcharge on FBA fulfilment fees from 17 April 2026, and a festive peak fulfilment fee on selected FBA orders delivered from 15 October 2026 to 14 January 2027.
The five products, in Amazon’s own figures
| Product | Tier | 2025 | 2026 | Change |
|---|---|---|---|---|
| Vent cover filter 18 × 17.75 × 2.75 in, SIPP | Small Bulky | $10.31 | $9.57 | −$0.74 |
| Baby cot 24 × 7.5 × 6 in, not SIPP | Small Bulky | $12.27 | $12.18 | −$0.09 |
| Shoe storage bench 47.5 × 17.25 × 4.38 in, SIPP | Large Bulky | $17.71 | $18.77 | +$1.06 |
| Book shelf 37.58 × 12.27 × 5.74 in, not SIPP | Large Bulky | $20.74 | $23.08 | +$2.34 |
| Bulletin board 96 × 48 × 7 in | Overmax | $33.55 | $50.55 | +51% |
The pattern in these five examples: the two products that dropped from Large Bulky into the new Small Bulky tier came out ahead or roughly flat. The two that stayed Large Bulky paid more, whether or not they were SIPP-enrolled. And any Extra-Large item up to 150 lb over 96 inches on its longest side, or over 130 inches in length plus girth, picked up an Overmax handling fee. On the bulletin board above (96 × 48 × 7 inches), that fee added about half again to its fulfilment cost. Five examples are not an average: Amazon says its fulfilment fees fall by an average of $0.26 per unit for Large Bulky and $2.06 for Small Bulky, and that most bulky products already using SIPP see a net reduction.
The packaging fee, in full
Priced on dimensional weight rather than shipping weight, because dimensions determine the packaging required. Amazon states it averages $2.07 per unit.
| Dim weight | Fee | Dim weight | Fee |
|---|---|---|---|
| 0–5 lb | $1.51 | 25–30 lb | $3.47 |
| 5–10 lb | $1.68 | 30–35 lb | $3.60 |
| 10–15 lb | $1.97 | 35–40 lb | $3.78 |
| 15–20 lb | $2.60 | 40–45 lb | $3.80 |
| 20–25 lb | $2.92 | 45+ lb | $4.04 |
The 2-inch minimum nobody mentions
For Small Bulky, Large Bulky, Overmax and Extra-Large items, Amazon assumes a 2-inch minimum on width and height regardless of how flat the product is. Amazon’s own example makes the point:
A white dry erase board, 40 × 1 × 25 inches, unit weight 4.5 lb. Dimensional weight is calculated as 40 × 2 × 25 ÷ 139 = 14.4 lb, because the 1-inch depth rounds up to the 2-inch minimum.
A 4.5 lb board billed as 14.4 lb. Flat products get no reward for being flat once they’re in a bulky tier — which means shaving depth below two inches buys you nothing there, and the effort belongs on length and width instead.
What to do about it
- Pull the Fee Preview report and check the tier column. Anything in Small Bulky or Large Bulky needs looking at.
- For every bulky SKU, work out whether SIPP pays. If the packaging fee for your dimensional band exceeds the cost of SIPP certification, enrol. At $1.51 to $4.04 a unit, that’s usually a fast decision.
- Find the SKUs sitting just over a boundary. Small Bulky caps at 37 inches longest, 28 median, 20 shortest, 130 length plus girth. An inch of carton redesign moves a product into a cheaper tier permanently.
- Check the 96-inch line. Overmax adds a handling fee of $17, $21 or $25, depending on weight, on top of the fulfilment fee.
- Re-run break-even ACoS. A $2.34 increase on a $40 product takes about six points off your break-even. Campaigns that were profitable before 15 January 2026 may not be under the 2026 rates.
We re-tier catalogues for a living
Our audit maps every SKU against the 2026 tier boundaries, models the SIPP decision per product, and flags the ones where a packaging change pays for itself.
Prepared by Ecom Enable. All figures are Amazon’s own published comparisons and rate cards, verified 27 August 2026 and re-checked on 10 October 2026 against Amazon’s published fee pages and announcements (US, plus UK and Europe for the paragraph on the UK). US marketplace only. Amazon’s US non-peak rate cards for 2026 start on 15 January (Amazon reports no US fee increase in 2025); US peak rates apply from 15 October 2026 to 14 January 2027.