Amazon FBA Fees at 4 oz vs 8 oz vs 16 oz

A 16 oz Small Standard unit is not a heavier version of the same FBA fee. On the 2026 $10–$50 card the cell itself moves: $3.42 at 4 oz, $3.54 at 8 oz, $3.96 at 16 oz — then the 3.5% fuel surcharge multiplies whichever cell you landed on.

Switch the Amazon FBA Calculator to Small Standard and type 0.25, 0.50, then 1.00 lb on a $29.99 Home & Kitchen listing. The fulfillment row is the only line that should move. The $10 / $50 price bands are a different toggle — that walkthrough is Amazon FBA low-price fees.

Eight ounce cells, one price band

Small Standard is the FBA tier for packaged units up to 15″ × 12″ × 0.75″ and 16 oz. Inside that envelope the 2026 US card still charges by shipping weight in 2 oz steps. Price band is a second axis: this page stays in the $10–$50 column because $29.99 sits there and $14.99 still does. Under $10 and over $50 use the other two numbers in the same amazon.ts row.

Small Standard · $10–$50 card · base fulfillment (before 3.5% fuel)

Shipping weight	Base FBA	After fuel	Dataset cell
4 oz (0.25 lb)	$3.42	$3.54	`upTo4oz.mid`
8 oz (0.50 lb)	$3.54	$3.66	`upTo8oz.mid`
12 oz (0.75 lb)	$3.78	$3.91	`upTo12oz.mid`
16 oz (1.00 lb)	$3.96	$4.10	`upTo16oz.mid`

Cells are amazon.ts fbaFulfillmentFees.smallStandard, last verified 2026-10-01. Fuel is fuelSurchargeMultiplier (1.035). Apparel and DG cards are not in this file — verify those SKUs in Seller Central.

The 4 → 16 oz climb is $0.54 of base fulfillment ($0.56 after fuel on a $29.99 listing). That is an insert, a gift box, or a spare in the same envelope — not a new size tier. Leave the 0.75″ thickness cap or 16 oz and you are no longer on this card: Large Standard’s 16 oz mid cell is $4.60, $0.64 above $3.96 before fuel. The ounce cells under 1 lb on that tier are Amazon FBA Large Standard fees at 4 oz vs 8 oz vs 12 oz; the pound ladder from 1.00 lb is Amazon FBA fees at 1 lb vs 2 lb vs 3 lb.

SKU A: $29.99, calculator defaults, only ounces change

SKU A is the calculator’s default Home & Kitchen listing with the size tier flipped: $29.99, $8.00 COGS, $1.00 inbound, 0.25 cu ft, one off-peak month of storage ($0.78/cu ft → $0.20). Referral stays 15% ($4.50; the $0.30 minimum is not binding). Storage is held constant so the table isolates the fulfillment jump.

Home & Kitchen, $29.99, Small Standard. Fulfillment rises $0.56 from 4 oz to 16 oz; profit falls by the same amount because referral, storage, inbound, and COGS are unchanged. Scroll sideways on small screens.

SKU A · Home & Kitchen · $29.99 · $8.00 COGS · $1.00 inbound · 0.25 cu ft × $0.78

Weight	Referral (15%)	FBA + fuel	Storage	Profit / unit	Margin
4 oz	$4.50	$3.54	$0.20	$12.76	42.5% · healthy
8 oz	$4.50	$3.66	$0.20	$12.63	42.1% · healthy
16 oz	$4.50	$4.10	$0.20	$12.20	40.7% · healthy

Profit = price − referral − FBA − storage − inbound − COGS. Reproduce the three rows in the calculator with Small Standard + Home & Kitchen + $29.99. The 8 → 16 oz step ($0.43) is larger than 4 → 8 oz ($0.12).

On this mid-ticket SKU the 16 oz version is still 40.7% · healthy. Weight is a packaging project, not a kill switch: $0.56 per unit is what a 4 oz redesign is worth before you spend it on a new carton. Crossing $10 on the same 4 oz cell is the other axis — $2.49 vs $3.42 before fuel — and lives on the low-price page.

SKU B: $14.99 / $8 COGS — 8 oz already loses

Same Small Standard path, tighter contribution. $14.99 still sits in the $10–$50 fulfillment column, so the FBA cells are identical to SKU A. Referral is 15% of the lower sticker ($2.25). COGS stays $8.00. The ounce jump now crosses zero.

SKU B · Home & Kitchen · $14.99 · $8.00 COGS · same inbound and storage

Weight	Referral (15%)	FBA + fuel	Profit / unit	Margin
4 oz	$2.25	$3.54	$0.01	0.0% · thin
8 oz	$2.25	$3.66	-$0.12	-0.8% · loss
16 oz	$2.25	$4.10	-$0.55	-3.7% · loss

Same calculator path as SKU A: change price to $14.99 and keep cost at $8.00, then step the weight. 4 oz is already 0.0% · thin; 8 oz is -0.8% · loss.

If A, a 16 oz inbound on the $29.99 / $8.00 SKU still clears 40.7% — cut weight when the carton project is cheaper than $0.56 per unit. If B, do not send the 8 oz or 16 oz version at $14.99 / $8.00: the 8 oz row is already -$0.12 per unit. Raise the sticker, cut COGS, or drop the SKU. Volume does not fix a negative unit.

If A, redesign the insert / if B, do not inbound

The rule is not “heavier products cost more.” It is two forks on the same Small Standard card — re-run your own price, COGS, and cube in the calculator before you copy the dollars.

If leftover after 15% referral, COGS, inbound, and storage still clears 25% at 16 oz (SKU A) — inbound is fine. Spend the packaging budget only when a real path back to 4 oz (or 8 oz) is cheaper than $0.56 per unit. Do not chase Large Standard math on this page; once the box is thicker than 0.75″ you have left the envelope and the 1 lb / 2 lb / 3 lb table applies.
If leftover is already thin at 4 oz (SKU B) — stop. The 8 oz cell is $0.12 more fulfillment on the same sticker, and that is enough to flip $0.01 into -$0.12. Re-price or re-source before the first inbound. Peak storage ($2.40/cu ft in Q4 vs $0.78 off-peak) is a separate lever on Amazon Q4 2026 prep.

Comparing the same SKU on another marketplace is the Marketplace Fee Comparison Calculator, not this ounce table. The 3.5% fuel line that sits on every cell is already inside the calculator’s fulfillment row.

How to run the number this week

Open the Amazon FBA Calculator. Set Small Standard, Home & Kitchen (or your real category), your COGS and inbound, and January–September storage unless the unit will sit into Q4.
Enter the live list price. Set weight to the packed shipping weight Amazon will use in pounds — 0.25 for 4 oz, 0.50 for 8 oz, 1.00 for 16 oz. Write down Net profit / unit at the current pack-out, then at the next cell a carton or insert change could actually hit. On SKU A those three figures are $12.76, $12.63, and $12.20.
If you change cartons often, watch the live dimensional-weight line, not the factory spec. Helium 10 ^* is the research suite we already link from the calculator; Sellerboard ^* is the per-SKU settlement view. Neither changes the fee card.
Confirm the 4 / 8 / 16 oz row in Seller Central’s Revenue Calculator before you lock a packaging redesign. This page follows amazon.ts (https://sellercentral.amazon.com/help/hub/reference/external/G201411300). Apparel, oversize, and dangerous-goods cards are outside this file.

Frequently asked questions

How much more does Amazon FBA charge at 16 oz than at 4 oz on Small Standard?

On the 2026 Small Standard $10–$50 card, the base cell is $3.42 at 4 oz, $3.54 at 8 oz, and $3.96 at 16 oz. After the 3.5% fuel surcharge those become $3.54, $3.66, and $4.10 — $0.56 more fulfillment from 4 oz to 16 oz on the same selling price. Apparel and dangerous-goods cards are separate. Verify the live cell in Seller Central’s Revenue Calculator.

Does a 16.1 oz packaged unit stay on the Small Standard card?

No. Small Standard stops at 16 oz and at 15″ × 12″ × 0.75″. Anything heavier, or a tenth of an inch thicker than 0.75″, leaves this page’s card. The next weight on Large Standard at 16 oz is the $4.60 mid-band cell — $0.64 above Small Standard’s $3.96 16 oz cell before fuel. Large Standard’s ounce cells under 1 lb are Amazon FBA Large Standard fees at 4 oz vs 8 oz vs 12 oz; the pound ladder from 1.00 lb is Amazon FBA fees at 1 lb vs 2 lb vs 3 lb.

How do I reproduce the 4 oz / 8 oz / 16 oz table in the calculator?

Open the Amazon FBA Calculator. Leave $29.99 price, $8.00 cost, Home & Kitchen, $1.00 inbound, January–September storage, 0.25 cu ft, 1 month. Switch Product Size Tier to Small Standard. Set weight to 0.25 lb (4 oz), then 0.50 lb (8 oz), then 1.00 lb (16 oz). Net profit / unit should match $12.76, $12.63, and $12.20.

Is the $10 Low-Price column a bigger jump than 4 oz to 16 oz?

On this 4 oz cell, leaving the under-$10 column is $0.93 of base fulfillment ($2.49 → $3.42). Climbing 4 oz to 16 oz on the $10–$50 card is $0.54 ($3.42 → $3.96). They are different axes: price band vs shipping weight. Reproduce the $10 toggle on Amazon FBA low-price fees; keep this page for the ounce ladder.

Does the 3.5% fuel surcharge change between 4 oz and 16 oz?

The rate does not. The 3.5% fuel & logistics surcharge (effective 2026-04-17) multiplies whichever Small Standard cell you land on. Heavier units pay more dollars of surcharge because the base is higher — $0.14 on the 16 oz cell versus $0.12 on the 4 oz cell in this example — but it is the same multiplier. The calculator’s fulfillment row already includes it.