How to Print FBA Labels: FNSKU Item Labels and Box Labels, Step by Step

Every FBA shipment needs two completely different labels, printed at two different points in the workflow. The FNSKU item label goes on each individual unit and must be printed between 1 x 2 inches and 2 x 3 inches, in black on white non-reflective stock, at 300 DPI or higher. The FBA box ID label goes on the outside of each carton and prints at 3 1/3 x 4 inches, or 4 x 6 inches if you select thermal printing paper. Item labels come from Manage Inventory or the Send to Amazon workflow; box labels are generated by the shipment workflow itself and are unique per box. Every specification below is quoted from a publicly readable Seller Central help page, linked at the point of use, checked 2026-09-03.

This guide covers the print-and-apply operation only. If you are still deciding which barcode type your listing needs, start with Amazon barcode requirements. If you need per-category prep rules such as poly bagging and suffocation warnings, those live in FBA prep requirements.

The Two Labels: FNSKU Item Label vs. FBA Box ID Label

Most rejected shipments trace back to a seller treating these as one job. They are not. They have different sizes, different generation points, and different failure modes.

Two label types sit outside this article’s scope: carrier labels (UPS, FedEx, or your small parcel carrier), generated by the carrier or Amazon’s partnered carrier flow, and pallet labels for LTL/FTL freight — four per pallet, one on the top center of each side, covered in FBA pallet requirements.

FNSKU Label Specs Amazon Actually Publishes

These come from the Seller Central page Use Amazon barcodes for FBA, checked 2026-09-03. Where Amazon does not publish a number — font size, for instance — none is listed here.

Amazon also states that its fulfillment centers “currently use Zebra GX430t model printers with a direct thermal setting” — a useful compatibility benchmark when choosing hardware.

For laser printing, Seller Central generates a PDF sized to set sheet layouts: 30 per page (1 inch x 2 5/8 inches on US letter) is the common US format, alongside A4 layouts at 21, 24, 27, 40, and 44 per page. If your driver tries to resize the PDF, set scaling to None or 100% — a scaled label falls outside the size range and can push the quiet zones below the published minimums.

One clause is easy to miss: labels printed directly onto product packaging must meet the same requirements. Direct-print does not exempt you from the quiet zones or the content fields.

How to Print Item Labels in Seller Central

Amazon documents two entry points. Both produce the same label.

From Manage Inventory, per the same help page:

1. Select the products in the left column.
2. Choose Print item labels from the Select group action drop-down menu.
3. Choose standard or thermal format when the label printing pop-up appears.

From the Send to Amazon workflow:

1. In step 1, if a SKU requires Amazon barcodes, click Print SKU labels in the Information/action column and apply the printed labels.
2. Alternatively, click Print all SKU labels at the end of step 1 to print every unit label for the shipment at once.
3. Unit labels can also be reprinted from View contents in each shipment card in steps 2 through 5.

Every menu name above is quoted from Seller Central’s own help page rather than from a screenshot; this guide does not describe screens behind the login wall.

Two operational notes. The item condition printed on the label is translated to match your Seller Central language preference, but the product name is not — worth checking if you run the account in a non-English language and ship to a US fulfillment center. And because the FNSKU is stable for the life of the SKU, item labels can be printed in bulk ahead of a shipment; box labels cannot.

If you are labeling at volume rather than by hand, FBA prep software compares the tools that batch this step.

How to Print and Place Box Labels

Box labels are generated only inside the shipment creation workflow, and every label is unique to one carton. The rules below come from Shipping label requirements, checked 2026-09-03.

Sizes. Labels support 8.47 x 10.16 cm (3 1/3 x 4 inches). With a thermal printer you can print directly on 10 x 15 cm (4 x 6 inches) by selecting thermal printing paper in the box and pallet label printing options.

Placement rules published on that page:

• Print the full set of labels. Because each label is unique, do not photocopy, reuse, or modify labels for use on additional boxes.
• Do not place labels on a seam or opening on the box, because they will be damaged when the box is opened.
• Place both the FBA box ID label and the carrier label on a flat surface of the box so the barcodes do not fold over the edges or corners.
• Both labels must remain uncovered so they are scannable and readable.
• Each box in the shipment must have its own FBA box ID label printed from your shipment workflow.
• If you are shipping multiple case packs in a larger box, apply the FBA box ID label to the larger box. You do not need to apply labels to the individual case packs.

Amazon is blunt about the consequence: “Failure to label your boxes with the required FBA box ID label may lead to blocking of future shipments.” The same page also notes that 2D barcodes used to transmit box content information do not replace FBA box ID labels — if you use them, you still print and apply the box labels.

Printer rules mirror the item-label rules: thermal optimized, laser supported, inkjet not permitted, scaling at none or 100%. Full inbound sequencing is covered in how to ship to Amazon FBA.

Two 2026 Changes That Alter Who Has to Label

Both of these change the labeling workload for a large share of sellers, and both are recent enough that older guides still describe the previous state.

As of March 31, 2026, resellers must apply Amazon barcodes. Amazon is ending commingling. Per the FBA barcode choice and labeling FAQ, brand owners holding the Brand Representative role in Brand Registry can continue stickerless with manufacturer barcodes, while resellers “are now required to use Amazon barcodes for products even if they have a manufacturer barcode.” Inventory received from resellers without Amazon barcodes after that date is considered defective, and the FAQ states that units not properly labeled in compliance with the requirements are not eligible for reimbursement. Stock already in or in transit to fulfillment centers before March 31, 2026 needs no action. Amazon is also waiving the low-inventory-level fee at the FNSKU level in the US, Canada, Germany, France, Italy, and Spain stores during the transition.

As of January 1, 2026, Amazon no longer labels units for you. The FBA Label Service page states that “Effective January 1, 2026, we’ll no longer offer prep and item labeling services,” with the prior $0.55 per unit rate honored only for shipments created before that date. The practical effect: outsourcing FNSKU application is now a third-party prep centre decision, not a checkbox in the shipment workflow.

Labeling Mistakes That Get Units Marked Defective

Amazon publishes the exact problem categories that surface in your Shipping Queue. Each maps to a physical mistake at the label-and-pack stage.

The placement rules that prevent these are specific:

• Cover all other visible barcodes on the unit, with two exceptions: serial number barcodes and Transparency authentication codes stay exposed.
• Never label a curve or a corner. A barcode bent across an edge is the single most common scan failure.
• Leave 0.25 inch between the edge of the label and the edge of the packaging.
• Check scannability after prep. Amazon requires the barcode to remain scannable once prep materials are applied, so rescan a sample through the finished packaging. The matching rule on the prep side — bags must be transparent and the label readable on the outside of the bag — is covered in FBA prep requirements.
• Label every unit in a case pack and remove any barcodes on the case itself.
• Reprint rather than reuse. Box labels are unique per carton; photocopying one is a direct violation, not a shortcut.

When a unit that requires an Amazon barcode arrives without one, Amazon marks it defective, applies a barcode sticker itself, and reports the defect on your Inbound Performance Dashboard. That is a recorded inbound defect against your account, not a free fix. For the wider set of avoidable inbound charges, see FBA mistakes that cost real money.

Pre-Ship Labeling Checklist

Run this before the boxes are taped shut.

• Barcode preference confirmed per SKU — manufacturer barcode only if the product is eligible and your brand relationship supports it
• Item labels printed at 300 DPI or higher, sized within 1 x 2 in to 2 x 3 in
• Printer scaling set to None or 100%, and a test label scanned before the full run
• Every other visible barcode covered, except serial numbers and Transparency codes
• No label on a curve, corner, seam, or opening
• 0.25 inch clear between label edge and package edge
• Barcodes rescanned after poly bagging or other prep
• One unique FBA box ID label per carton, printed fresh from the shipment workflow
• Box ID label and carrier label both on flat surfaces, both uncovered
• Four pallet labels per pallet for LTL/FTL, one on the top center of each side

Frequently Asked Questions

What size should an FNSKU label be?

Between 1 x 2 inches and 2 x 3 inches — Amazon gives 1 x 3 inches and 2 x 2 inches as valid examples within that range. It must be black ink on white, non-reflective stock with removable adhesive, printed at 300 DPI or greater, per Seller Central’s Amazon barcode page checked 2026-09-03.

Can I use a regular office printer for FBA labels?

A laser printer, yes. Amazon supports laser printing and generates sheet-format PDFs for it. An inkjet printer, no — the help pages for both item labels and box labels state that inkjet printers must not be used. Amazon does not publish a reason, but it does list smudged or smeared print as a scan-failure cause and requires every label to stay readable and scannable for 24 months.

Do I need a thermal printer for FBA?

Not strictly. Amazon says its tools are optimized for thermal printers but that laser printers also work. The practical advantage of thermal is the 4 x 6 inch box label format and the absence of consumable ink; Amazon notes its own fulfillment centers run Zebra GX430t printers on a direct thermal setting.

Why did my units arrive at Amazon marked defective?

The most common causes Amazon reports are a missing barcode, a barcode that does not match the physical product, or a barcode that could not be scanned because it was smudged, wrapped around a corner, or printed on a reflective surface. Since March 31, 2026, reseller inventory sent without an Amazon barcode is also treated as defective.

Can I reuse or photocopy an FBA box label?

No. Each FBA box ID label is unique to one carton. Amazon’s shipping label requirements page instructs sellers to print the full set and not to photocopy, reuse, or modify labels for additional boxes, and warns that failure to apply the required box ID label may lead to blocking of future shipments.

Where This Fits in Your Inbound Process

Labeling is the last reversible step before a shipment leaves your hands. Barcode type is decided at the listing level, prep is decided by category, and both are settled before you print anything — but a correctly prepped unit with a bent, scaled, or photocopied label still arrives as a defect. Print at 300 DPI, keep the label flat and inside the size range, give every carton its own box ID label, and scan a sample before you seal.

For the decision layer above this one, see Amazon barcode requirements; for the physical prep layer beside it, see FBA prep requirements; and for how carton dimensions feed into your fulfillment cost, see FBA size tiers.