Do I Need a Barcode for Amazon FBA? (FNSKU vs EAN/UPC Explained)

If you're sending products into Amazon FBA, you will absolutely need barcodes — but not always the type you think.

This is where many ecommerce sellers get confused:

Do you need an EAN or UPC?
What is an FNSKU?
When does Amazon relabel your products?
Do cartons need separate barcodes?
What about GTIN exemptions?

Let's break this down clearly so you can ship to FBA without delays, extra fees, or stranded inventory.

1. FNSKU vs Manufacturer Barcode (EAN/UPC)

What is an FNSKU?

An FNSKU (Fulfilment Network Stock Keeping Unit) is an Amazon-specific barcode used to identify your product inside Amazon's warehouses.

It's unique to:

Your seller account
That specific ASIN
That specific fulfilment channel

Even if two sellers sell the exact same product, their FNSKUs will be different.

What is a Manufacturer Barcode?

This is your standard retail barcode, such as:

GS1-issued EAN-13
GS1-issued UPC-A

These are global retail identifiers (GTINs) used outside Amazon — in physical retail, other marketplaces, and ecommerce stores.

The Key Difference

Barcode Type	Used By	Required for FBA?
EAN / UPC	Global retail	Required to create listing (unless exempt)
FNSKU	Amazon internal	Required on units unless using manufacturer barcode

For most private-label sellers, FNSKU labelling is the safest route.

2. When Does Amazon Relabel Your Products?

Amazon will relabel your products if:

You ship inventory with only a manufacturer barcode
Your listing requires FNSKU tracking
You opt into Amazon's labelling service
Your labels are unreadable or placed incorrectly

If Amazon relabels your products, they charge per unit.

That adds up fast.

If you're scaling, relying on Amazon to fix labelling mistakes is sloppy operations. It eats margin and creates delays. Better to control your barcoding upstream.

3. When Should You Use EAN or UPC?

You need an EAN/UPC when:

Creating a new product listing (unless GTIN-exempt)
Selling outside Amazon
Selling internationally
Planning retail expansion

If you're serious about building a brand (not just flipping), buy your barcodes directly from GS1 in your country. Avoid resellers.

Amazon increasingly verifies GTIN ownership. Cheap barcodes often cause listing suppression later. See How to Get a GS1 Barcode for the correct approach.

Think long-term.

4. FNSKU vs Manufacturer Barcode in FBA (Stickered vs Commingled)

When creating your FBA shipment, Amazon gives you two options:

Option A: Use Manufacturer Barcode (Commingled Inventory)

Amazon mixes your inventory with other sellers
They use the EAN/UPC to track
You may receive returned units from other sellers

This is rarely recommended for private-label brands.

Option B: Use Amazon Barcode (FNSKU)

Your units remain separate
Full control over authenticity
Safer for brand protection

For 95% of branded sellers, choose FNSKU.

5. Carton Labelling for Amazon FBA Shipments

Individual units need:

FNSKU label (if required)
Or visible manufacturer barcode (if approved)

Shipping cartons need:

Amazon shipment label (PDF generated in Seller Central)
Box ID label
Correct placement on flat surface
No overlapping tape or seams

If you're shipping pallets:

Pallet labels on all four sides

Carton labels are separate from product barcodes. Don't confuse the two. For outer carton barcodes outside Amazon (ITF-14, GS1-128), see Carton Barcodes: ITF-14 vs GS1-128.

If cartons are missing proper labelling, your shipment can be:

Delayed
Refused
Sent to "problem solve"
Charged manual processing fees

Operational discipline here matters.

6. How GTIN Exemptions Work

Amazon allows GTIN exemptions if:

You manufacture your own products
You don't have GS1 barcodes
You sell handmade or custom goods
You're reselling products without standard GTINs (in some cases)

You apply inside Seller Central under:

Catalog → Apply for GTIN exemption

If approved:

You can create listings without EAN/UPC
Amazon still generates an FNSKU

Important: GTIN exemption ≠ no barcode required.

You still need FNSKU labels on each unit.

7. Common FBA Barcode Mistakes

Here's what causes problems:

Printing FNSKU over existing barcode without fully covering it
Using low-resolution label printers
Placing label on curved surface
Sending units with both barcodes scannable
Not matching FNSKU to correct ASIN variation

These mistakes lead to stranded inventory and expensive removals.

Don't treat labelling like an afterthought.

Final Answer: Do You Need a Barcode for Amazon FBA?

Yes.

You need:

A GTIN (EAN/UPC) to create listings — unless exempt
An FNSKU label on each unit — unless using manufacturer barcode
Amazon carton labels for every shipment

If you're scaling, the smart setup is:

Proper GS1 GTIN
FNSKU applied at factory
Cartons labelled before leaving supplier

That's how you avoid operational friction.

FAQ: Amazon FBA Barcodes

Do I always need an FNSKU for Amazon FBA?

Yes, unless you are approved to use manufacturer barcode (commingled inventory). Most private-label sellers should use FNSKU.

Can I use the same UPC for Amazon and retail?

Yes. A GS1-issued UPC or EAN can be used globally — on Amazon, retail stores, and ecommerce — as long as it's correctly registered.

What happens if I don't label my FBA products?

Amazon will relabel for a fee, delay processing, or mark inventory as unfulfillable.

Is GTIN exemption permanent?

It depends on the category and approval. Amazon may request brand documentation or revoke exemption if policies change.

Can I switch from manufacturer barcode to FNSKU later?

Yes. You can change settings in Seller Central, but all future shipments must match the selected method.

Do cartons need EAN or FNSKU labels?

No. Cartons require Amazon shipment labels (not retail barcodes). Master cartons outside Amazon may use ITF-14 or GS1-128, but that's separate from FBA shipment labelling.

If You're Growing Beyond Amazon…

If you're serious about building a real brand — not just an Amazon listing — your barcode system needs to work:

For FBA
For wholesale
For international retail
For 3PL fulfilment

The sellers who scale treat barcodes and SKU structure like infrastructure, not admin.

And that's exactly where most operational chaos starts.

Fix it early.

Still unsure which barcode format your product needs? Read GTINs Explained and Which Barcode Should I Use?.