Seller Glossary

1099-K

The IRS form marketplaces issue reporting your gross payment volume.

3PL

Third-party logistics — outsourced warehousing and fulfillment.

A+ Content

Enhanced product-page modules (images, comparison charts) for Brand Registry sellers.

Accrual accounting

Recording revenue when earned and costs when incurred — not when cash moves.

ACOS

Advertising Cost of Sales — ad spend divided by ad-attributed revenue on Amazon.

Aged inventory surcharge

Extra FBA fees on units stored beyond age thresholds.

Amazon reserve

Funds Amazon temporarily holds back from a payout, released in later settlements.

Amazon Vine

Amazon's invite-only early-review program for new products.

ASIN

Amazon Standard Identification Number — Amazon's unique ID for every product in its catalog.

Brand Registry

Amazon's program giving trademark owners brand protection and marketing tools.

BSR (Best Sellers Rank)

Amazon's sales-velocity rank for a product within its category.

Buy Box (Featured Offer)

The default 'Add to Cart' offer on an Amazon listing, shared among competing sellers.

Chargeback (Vendor)

Deductions Amazon takes from vendor (1P) payments for compliance failures.

Chart of accounts

The list of accounts (income, expense, asset, liability) your books are organized into.

Clearing account

A holding account that nets marketplace activity against bank deposits for clean reconciliation.

COGS

Cost of Goods Sold — the cost of the units you actually sold in a period.

Dropshipping

Selling products that a supplier ships directly to your customer.

FBA

Fulfillment by Amazon — Amazon stores, picks, packs, and ships your inventory.

FBA reimbursement

Money Amazon owes you when it loses, damages, or mishandles your FBA inventory.

FBM

Fulfilled by Merchant — you store and ship orders yourself.

FIFO

First-In, First-Out — inventory valuation that consumes the oldest cost layers first.

FNSKU

Fulfillment Network SKU — the barcode Amazon uses to track YOUR units in its warehouses.

Gross margin

Revenue minus COGS, as a percentage of revenue.

IPI (Inventory Performance Index)

Amazon's 0–1000 score of how efficiently you manage FBA inventory.

KDP

Kindle Direct Publishing — Amazon's self-publishing platform for ebooks and print.

Landed cost

The true per-unit cost of inventory: supplier price plus freight, duty, taxes, and prep.

Marketplace facilitator tax

Sales tax that the marketplace (Amazon/eBay/Etsy) collects and remits on your behalf.

MOQ

Minimum Order Quantity — the smallest order a supplier will accept.

Overselling

Selling units you don't actually have — the multichannel sync failure mode.

Prep center

A service that labels, bundles, and preps inventory to FBA requirements before inbound shipping.

Private label

Manufacturing a product under your own brand rather than reselling others'.

Purchase order (PO)

The formal order you place with a supplier — and the source of true unit cost.

Referral fee

Amazon's commission on each sale, typically 8–15% depending on category.

Removal order

An instruction for Amazon to return or dispose of your FBA inventory.

Reorder point

The stock level that should trigger a new purchase order — velocity × lead time + safety stock.

Safety stock

Buffer inventory held against demand spikes and supplier delays.

Sales tax nexus

A connection to a state that creates sales-tax obligations there.

Seller Fulfilled Prime

Prime badge on orders you ship yourself, under strict performance requirements.

Settlement

The statement behind each marketplace payout, listing every transaction that produced the deposit.

SKU

Stock Keeping Unit — the seller-defined identifier for a product you sell.

Split shipment

Amazon dividing one inbound shipment across multiple fulfillment centers.

Stranded inventory

FBA stock in the warehouse with no active listing selling it.

TACOS

Total Advertising Cost of Sales — ad spend divided by TOTAL revenue, not just ad-attributed.

Ungating

Getting approval to sell in a restricted Amazon category or brand.

Weighted average cost

Inventory valuation method that recalculates a blended unit cost on every receipt.