FBA Operations for Beginners: Prep, Labeling, Shipments, and Inventory Controls

What “FBA Operations” Means in Practice

FBA operations is the repeatable workflow you use to turn products you own into sellable, traceable inventory inside Amazon’s fulfillment network. The goal is simple: every unit must be identifiable (SKU/ASIN), scannable (barcode), prepped correctly (packaging rules), shipped correctly (cartons and pallet rules), and monitored after check-in (receiving, stranded, aged, and replenishment decisions). Small setup mistakes can create expensive outcomes: commingled inventory issues, stranded listings, receiving shortages, or long-term storage/aged inventory fees.

Key identifiers you’ll use

• ASIN: Amazon’s catalog identifier for a product detail page.
• SKU: Your internal identifier for an offer; you control it. One ASIN can have multiple SKUs (e.g., different suppliers, bundles, or prep types).
• FNSKU: Amazon’s barcode that ties a physical unit to your specific seller account/offer.
• UPC/EAN/GTIN: Manufacturer barcode used for retail identification; sometimes used for commingled inventory if enabled and eligible.

End-to-End Workflow: From SKU Creation to Inventory Check-In

Step 1: Create a SKU that supports operations (not just bookkeeping)

A good SKU helps you diagnose problems later (receiving discrepancies, returns, supplier defects) and prevents mixing inventory sources. Use a consistent pattern that encodes the variables that matter.

Recommended SKU pattern (example): BRAND-PROD-SIZE-COLOR-SUP1-2026Q1-PREP1

• Supplier/source code (e.g., SUP1, SUP2) prevents mixing lots in your own records.
• Date/lot marker helps trace defects or compliance documents.
• Prep type (e.g., POLY, BUBBLE, LABEL) helps you repeat the same prep every reorder.

Practical example: You buy the same ASIN from two distributors. Create two SKUs (e.g., ACME-BOTTLE-20OZ-SUPA-2026Q1 and ACME-BOTTLE-20OZ-SUPB-2026Q1) so you can isolate issues if one source causes higher returns or authenticity complaints.

Step 2: Decide your barcode strategy (FNSKU vs manufacturer barcode)

Your barcode choice affects commingling risk and how Amazon attributes inventory.

Continue in our app.

You can listen to the audiobook with the screen off, receive a free certificate for this course, and also have access to 5,000 other free online courses.

Or continue reading below...

Download the app

Operational rule of thumb: If you want maximum control and traceability, use FNSKU labeling for every unit.

Step 3: Confirm packaging and prep requirements before you touch inventory

Prep is about making units “warehouse-safe” and “ship-ready” for Amazon’s automation. Requirements vary by category and product type, but the operational checks are consistent.

Core prep checks (apply to most products)

• Unit integrity: One sellable unit must stay together (no loose parts). If it can separate, secure it (bag, tape, or shrink).
• Barcode scannability: Exactly one scannable barcode should be visible for the unit you intend Amazon to scan. If the manufacturer barcode could be scanned by mistake, cover it when using FNSKU.
• Polybag rules: If polybagging, ensure the bag is sealed and the barcode is scannable through the bag or placed on the outside. Use suffocation warnings when required.
• Fragile protection: Use bubble wrap or appropriate protection so the unit survives inbound shipping and warehouse handling.
• Liquids and powders: Use leak-proof seals and secondary containment where needed; ensure caps are taped if required by the product’s risk profile.
• Expiration-dated items: Expiration dates must be printed in the correct format and visible; units may require additional labeling rules and have inbound restrictions.

Practical example: You’re sending a boxed glass bottle. Even if the retail box looks sturdy, add bubble wrap and ensure the FNSKU is on the outside of the wrapped unit (or scannable through the wrap). If the retail UPC is visible and you’re using FNSKU, cover the UPC to prevent mis-scan.

Step 4: Apply unit labels correctly (FNSKU labeling best practices)

Labeling is where many inbound problems start. Your goal is fast, error-free scanning at receiving.

• Place labels on a flat, visible surface (avoid seams, edges, curves).
• Do not cover critical product info (ingredients, warnings, compliance marks).
• Cover other scannable barcodes if using FNSKU (UPC/EAN, other FNSKUs).
• One unit = one FNSKU label unless Amazon specifically requires additional labels.
• Print quality: Use crisp printing; smudged thermal labels cause scan failures.

Quick test: Scan a random sample with a barcode scanner app. If it struggles, Amazon’s scanners may struggle too.

Step 5: Pack cartons with correct counts and consistent case packs

Carton packing affects receiving speed and discrepancy risk. Amazon expects what you declare in the shipment plan to match what arrives.

Units per case: why it matters

• If you send case-packed inventory, each carton must contain the same SKU and the same unit count per carton.
• If you send mixed-SKU cartons, you must provide accurate contents (and accept that mixed cartons can slow receiving).

Practical example: You plan 120 units and intend 6 cartons of 20. If you accidentally pack one carton with 18 and another with 22, Amazon may receive fewer units than you shipped, and reconciliation becomes harder.

Carton build best practices

• Standardize carton size per SKU when possible.
• Use internal dunnage to prevent movement and damage.
• Keep heavy items stable (avoid overpacking; prevent corner crush).
• Record carton-level data: carton number, SKU(s), units, weight, dimensions.

Step 6: Create the FBA shipment in Seller Central (workflow)

Shipment creation is where you translate your physical plan into Amazon’s expected inbound record.

1. Select the SKU(s) and quantities you are sending.
2. Choose prep responsibility (you or Amazon) and confirm any required prep/labeling prompts.
3. Set packing type: case-packed or individual/mixed units.
4. Enter carton information: units per carton, carton count, weights, and dimensions (as required).
5. Review destination(s): Amazon may split your shipment into multiple fulfillment centers. Plan your cartons accordingly.
6. Generate and print labels: unit labels (if needed) and carton/shipping labels.
7. Choose carrier and shipping method: small parcel delivery (SPD) vs less-than-truckload/full truckload (LTL/FTL).
8. Confirm shipment and schedule pickup/drop-off.

Operational tip: If Amazon splits your shipment, physically separate cartons by destination immediately and label staging areas (e.g., “FC A” and “FC B”) to prevent mislabeling cartons.

Step 7: Carton labeling (shipping labels) done right

Carton labels tell Amazon where each carton belongs and link it to your shipment ID.

• Use the correct label for the correct carton (destination-specific).
• Place labels on a flat side, not across seams or edges.
• Do not cover other carrier labels and do not place labels where tape will obscure barcodes.
• One carton = one unique carton label if Amazon provides unique labels.

Practical example: You print 12 labels for two destinations. Before applying, sort labels into two stacks by destination and count them. Then apply labels while cartons are staged in destination groups.

Step 8: Ship, track, and document proof of shipment

Tracking and documentation are your leverage if receiving discrepancies occur.

• Capture tracking numbers for every carton (SPD) or keep the BOL (LTL/FTL).
• Photograph key evidence: staged cartons with labels visible, packed carton interiors (sample), and pallet condition (if applicable).
• Keep a shipment file with: shipment ID, SKU list, carton counts, units per carton, carrier, ship date, and tracking.

Beginner Checklist: Avoiding the Most Common FBA Inbound Problems

1) Commingling risks (inventory mixing)

• Default to FNSKU labeling unless you intentionally accept commingling.
• Cover the manufacturer barcode when using FNSKU so Amazon scans the correct code.
• Do not mix sources under one SKU if you need traceability (use supplier-coded SKUs).

2) Incorrect units per case (case-pack errors)

• Decide case-packed vs mixed before packing.
• Count units per carton twice: once when packing, once when sealing.
• Use a carton packing sheet and sign/initial each carton count.

Carton Packing Sheet (example) Carton # | Destination | SKU | Units | Packed by | Verified by 001      | FC-A        | SKU123 | 20    | AB        | CD 002      | FC-A        | SKU123 | 20    | AB        | CD

3) Missing or wrong labels (unit or carton)

• Unit labels: spot-check 5–10% of units for correct FNSKU and scan readability.
• Carton labels: do a “final walk” before pickup—every carton must have the correct destination label and be scannable.
• Prevent label mix-ups: print labels per destination and apply in batches.

4) Stranded inventory (not sellable due to listing/offer issues)

Stranded inventory happens when units are physically in Amazon’s network but cannot be sold due to an offer, SKU, or listing condition problem.

• Before shipping: verify the SKU is active and the offer is buyable (correct condition, no closed listing).
• After shipping: monitor stranded inventory regularly and resolve root causes (pricing, suppressed offer, closed listing, condition mismatch).
• Operational habit: do not send replenishment to FBA if the SKU is currently stranded—fix sellability first.

5) Receiving discrepancies (Amazon receives fewer units than you shipped)

• Reduce discrepancy risk: accurate carton contents, consistent case packs, strong packaging to prevent damage/loss.
• Document everything: tracking, weights, carton counts, photos.
• Reconcile systematically: compare shipped units vs received units by shipment ID and by SKU; note which cartons were delivered when.

Practical approach: If you shipped 300 units and Amazon received 280, identify whether the shortage correlates to a specific delivery date, destination, or carton count. Your carton-level records make this possible.

Inventory Controls: Staying In-Stock Without Overbuying

Core metrics to track weekly

• On-hand FBA units: sellable inventory available.
• Inbound units: shipped but not yet received/available.
• Average daily sales (or weekly sales): your demand baseline.
• Lead time: time from reorder to inventory being sellable at FBA (supplier production + transit + receiving).
• Sell-through: how quickly inventory turns relative to what you hold.
• Aged inventory: units sitting too long, increasing fee risk and tying up cash.

Setting a reorder point (ROP) with a simple formula

Use a reorder point so you reorder before you stock out, accounting for lead time and variability.

Reorder Point (units):

ROP = (Average Daily Sales × Lead Time in Days) + Safety Stock

Example: You sell 8 units/day. Lead time to be sellable at FBA is 25 days. You keep 60 units as safety stock.

ROP = (8 × 25) + 60 = 260 units

When your sellable + inbound drops to ~260 units, place the next order.

Sell-through and buy quantity (how much to send)

Beginners often over-send to “save on shipping,” then get stuck with aged inventory. Instead, send based on a target coverage window.

Target coverage approach:

• Choose a coverage target (e.g., 30–45 days of sales at FBA).
• Send enough units to cover that window plus a buffer, considering inbound already on the way.

Example: Average weekly sales = 50. You want 6 weeks coverage (300 units). You already have 120 sellable and 60 inbound.

Needed = 300 - (120 + 60) = 120 units to send/order

Monitoring stranded inventory (weekly triage)

Create a weekly routine to catch stranded units early.

• Check stranded units and categorize: listing closed, pricing issue, condition mismatch, restricted offer, or other errors.
• Fix the cause before sending more inventory.
• Track time stranded: the longer it sits, the more it behaves like aged inventory (cash trapped).

Monitoring aged inventory (fee and cashflow control)

Aged inventory is inventory that has been sitting in fulfillment centers for extended periods. Even if it’s technically sellable, it can become expensive.

• Review aging buckets regularly and identify SKUs with slow movement.
• Take action early: adjust price, run promotions, improve conversion (images/copy), or stop replenishing.
• Stop sending more until you see consistent sell-through.

Removal vs disposal decisions (when inventory isn’t worth keeping)

When inventory is stranded, damaged, slow-moving, or approaching fee thresholds, decide whether to remove it back to you or dispose of it.

Operational rule: If you cannot confidently make the unit sellable within a short window, plan an exit (removal/disposal) rather than letting it age indefinitely.

One-Page FBA Shipment Quality Control (QC) Checklist

Before prep

• SKU naming includes source/lot info
• Barcode strategy chosen (FNSKU recommended for control)
• Prep requirements confirmed for the product type

During prep and labeling

• Units are secure (no loose parts)
• Fragile/liquid protection applied as needed
• FNSKU labels placed flat, scannable, and correct
• Other barcodes covered if using FNSKU
• Random scan test passed

Carton packing

• Case-pack counts are consistent (or mixed cartons documented)
• Carton packing sheet completed and verified
• Cartons are strong, sealed, and protected internally

Shipment creation

• Quantities match physical counts
• Correct packing type selected (case-packed vs mixed)
• Carton weights/dimensions entered accurately (when required)
• Destination split handled with separate staging

Carton labeling and handoff

• Correct destination label on every carton
• Labels placed flat; barcodes unobstructed
• Tracking/BOL saved; photos taken of labeled cartons
• Shipment file saved (shipment ID, cartons, counts, tracking)