Amazon Q4 2026 Prep: FBA Deadlines & Peak Storage Fees

Prime Big Deal Days inbound already closed on September 16 for Amazon-optimized splits. Black Friday stock still has to arrive by October 21 (minimal splits) or October 28 (Amazon-optimized) — and October 1 flips standard-size storage from $0.78 to $2.40 per cubic foot.

Type the SKU into the Amazon FBA Calculator, leave the $29.99 Large Standard defaults, and toggle the season. A 0.25 cu ft shoebox loses $0.41 on one peak month. A 1.0 cu ft carton that sits October–December loses $6.42 versus the same unit billed off-peak for one month. The $10 fulfillment-band math lives on Amazon FBA low-price fees; this page is the inbound calendar plus the storage toggle.

The remaining 2026 inbound ladder

Amazon had not posted a public 2026 cutoff in early July, when this page first shipped. The Holiday 2026 inbound note is now on Seller Forums (“Holiday 2026: Same fees, same eligibility, earlier deadlines”) and matches third-party recaps (PrepVia; FBA Prep Finder citing help reference G4QH4XCRWUXRJBLY). These are arrival targets for Prime-badge readiness, not hard rejection dates. Late freight can still check in — it just misses the event window. Confirm the live table in Seller Central before you book.

2026 FBA / AWD arrival targets · Seller Forums Holiday 2026 note

Event	AWD	FBA · minimal splits	FBA · Amazon-optimized
Prime Big Deal Days	September 2	September 9	September 16 · closed
Black Friday week + Cyber Monday	October 14	October 21	October 28 · most sellers

Black Friday 2026 is November 27; Cyber Monday is November 30. “Shipped by” the cutoff is not “received.” Q4 check-in queues run long — plan the truck so the FC scan happens on or before the date that matches your split option.

Planning anchors only. Peak storage ($2.40/cu ft, Oct–Dec) is the dataset rate; inbound dates are Amazon’s 2026 arrival targets. Confirm both in Seller Central.

Why the leftover cube is the Q4 fee, not the referral

Home & Kitchen referral stays 15% on a $29.99 sticker — $4.50 either season. The calculator-default Large Standard 1.5 lb mid-band fulfillment is $5.42 before the 3.5% fuel surcharge ($5.61 after). Neither line moves when the calendar flips to October. Storage does.

Amazon also lists a separate peak fulfillment surcharge window (mid-October through mid-January on the 2026 Holiday note). That per-unit add-on is not in amazon.ts, so this page does not invent a dollar. Verify the live surcharge on your size tier in Seller Central and add it on top of the calculator’s fulfillment row if your settlement shows it.

Calculator defaults · $29.99 · Home & Kitchen 15% · Large Standard 1.5 lb · $8.00 COGS · $1.00 inbound

Cube / season	Storage	Profit / unit	Margin
0.25 cu ft · 1 mo Jan–Sep	$0.20	$10.69	35.6% · healthy
0.25 cu ft · 1 mo Oct–Dec	$0.60	$10.28	34.3% · healthy
0.25 cu ft · 3 mo Oct–Dec leftover	$1.80	$9.08	30.3% · healthy
1.0 cu ft · 1 mo Jan–Sep	$0.78	$10.10	33.7% · healthy
1.0 cu ft · 1 mo Oct–Dec	$2.40	$8.48	28.3% · healthy
1.0 cu ft · 3 mo Oct–Dec leftover	$7.20	$3.68	12.3% · thin

Referral $4.50 and FBA + fuel $5.61 are identical on every row. The only moving fee is cubic feet × season rate × months. Peak leftover on 1.0 cu ft costs $7.20 versus $2.34 for the same three months off-peak — $4.86 extra. Aged-inventory dollars are omitted on purpose; they are not in the fee file.

Same carton, three bills. $2.40 × 3 months is the leftover you pay if the unit is still in the FC through December.

If A, send the event cover / if B, cut the bulky tail

The rule is not “it depends on your business.” It is two forks on the same $29.99 calculator SKU — re-run your own cube and sell-through before you copy the dollars.

If the leftover cube is a shoebox (0.25 cu ft). One peak month costs $0.41 versus off-peak; three peak months cost $1.61. Margin stays healthy (30.3%) on this SKU. Missing the October 21 / 28 arrival date costs the event. Do not cut inbound to save $1.80 of storage if that is the unit you actually sell in November.
If the leftover cube is 1.0 cu ft and it will sit October–December. Three peak months cost $7.20 and drop profit from $10.10 (33.7%, healthy) to $3.68 (12.3%, thin). That is $6.42 per leftover unit — larger than inbound on the default row. Order the event cover, not a “safe extra pallet,” and price a January removal if sell-through is a wish. Aged-inventory surcharge after day 181 is an extra line; verify it in Seller Central.

Q4 is also the heaviest advertising season. Higher CPCs on a thinner leftover margin move break-even ROAS. Run the post-storage profit through the Break-Even ROAS Calculator before you scale spend into the peak.

How to run the number this week

Open the Amazon FBA Calculator. Keep $29.99, $8.00, Home & Kitchen, Large Standard, 1.5 lb, $1.00 inbound — or type your real SKU.
Set cubic feet from L × W × H (inches) ÷ 1,728. Toggle January–September, then October–December. Set storage months to the weeks you honestly expect the leftover to sit, not the weeks you hope it sells.
If the peak-leftover row drops the SKU from healthy into thin (or loss), cut the inbound tail or raise the sticker. Packaging that drops a size tier is a different savings path — that list lives on 11 ways to reduce Amazon FBA fees.
Restock alerts and settlement views do not change the fee card, but they stop you from sending a second pallet into a SKU that is already going to sit. Helium 10 ^* is the research / restock suite already on the calculator; Sellerboard ^* is the per-SKU payout view.
Confirm the October 21 / 28 arrival date and the live storage rate in Seller Central before you lock the PO. This page follows amazon.ts (https://sellercentral.amazon.com/help/hub/reference/external/G201411300), last verified 2026-10-01.

Comparing the same SKU on a Shopify store instead of FBA is Amazon FBA vs Shopify and the Marketplace Fee Comparison Calculator. Those pages do not replace the Q4 storage toggle.

Frequently asked questions

When do Amazon FBA peak storage fees start in 2026?

October 1. Standard-size monthly storage in this dataset is $0.78 per cubic foot from January through September and $2.40 from October through December (3.1×). The rate applies to average daily volume on hand that month, not to the day the shipment arrived. A unit received in September that is still in the FC on October 1 is already on the peak card.

What are the official 2026 Black Friday FBA inbound dates?

Amazon’s Holiday 2026 inbound note (Seller Forums, corroborated by PrepVia and FBA Prep Finder against help reference G4QH4XCRWUXRJBLY) is an arrival target, not a rejection date: October 14 for AWD, October 21 for FBA with minimal shipment splits, October 28 for FBA with Amazon-optimized splits — the option most sellers pick. Prime Big Deal Days used the same ladder on September 2 / 9 / 16 and that window is already closed. Confirm the live calendar in Seller Central before you book a truck.

How do I reproduce the $29.99 peak-storage table in the calculator?

Open the Amazon FBA Calculator. Leave the defaults: $29.99 list, $8.00 product cost, Home & Kitchen, Large Standard, 1.5 lb, $1.00 inbound. Set cubic feet to 0.25 (shoebox) or 1.00 (about 18×12×8 in). Toggle January–September vs October–December and set storage months to 1 or 3. Net profit / unit should match $10.69 / $10.28 / $9.08 on the shoebox and $10.10 / $8.48 / $3.68 on the 1.0 cu ft carton.

Does leftover Q4 FBA inventory also get an aged-inventory surcharge?

Monthly peak storage and aged-inventory surcharge are separate lines. Peak storage is the October–December cubic-foot rate on this page. Aged-inventory surcharge is a different clock that starts after units sit past 181 days; the dollar bands are not in our fee file. Verify the current aged-inventory table in Seller Central before you treat spring leftover as free to hold. If a SKU will still be in the FC in April, price the removal or liquidation path now.

Did I miss Prime Big Deal Days inbound for 2026?

If the shipment was not at Amazon by September 16 (Amazon-optimized splits) or September 9 (minimal splits), yes — that inbound window is closed. Air freight can still put units into the FC for the October event, but it is a landed-cost decision, not a fee-card change. Black Friday inventory is the remaining published arrival ladder: October 21 or October 28 depending on your split option.