Amazon FBA Labeling Requirements 2026: Complete Guide for Sellers

<p>Incorrect labeling is one of the most common reasons Amazon sellers run into warehouse problems. A wrong barcode, missing label, or badly placed sticker can cause delays, extra fees, or rejected shipments. Here is what sellers need to know about FBA labeling requirements in 2026.</p><h2>FNSKU vs ASIN</h2><p>Amazon uses two main barcode systems:</p><p><strong>FNSKU, Fulfillment Network Stock Keeping Unit.</strong> This is Amazon's internal barcode for FBA inventory. Every unit sent to FBA should carry the correct FNSKU label tied to your account and listing.</p><p><strong>ASIN, Amazon Standard Identification Number.</strong> This is the generic Amazon product identifier. If you sell the same ASIN as other sellers, Amazon may commingle inventory unless you use FNSKU labeling.</p><p><strong>Important:</strong> unless you have intentionally enrolled in commingled inventory, FNSKU is usually the safer choice for FBA shipments.</p><h2>Where Do You Get FNSKU Labels?</h2><p>You can print them from Seller Central:</p><ol><li>Go to Inventory > Manage Inventory</li><li>Open the menu next to the product</li><li>Select Print Item Labels</li><li>Choose your label format, usually 30-up or 1-up</li></ol><p>If you work with a prep center like SNS Prep Center, you can provide the ASINs and have the FNSKU labels generated and applied for each unit.</p><h2>Label Placement Rules</h2><ul><li>standard products: place the FNSKU on the outside of the packaging and cover old barcodes</li><li>poly-bagged items: place the label on the outside of the bag</li><li>bundled items: place the label on the outer bundle packaging</li><li>expiration-dated products: never cover the expiration date</li><li>labels must stay flat and scannable, not wrapped over corners</li></ul><h2>Label Format and Size</h2><ul><li>common format: Avery 5160, 1 x 2-5/8 inches, or equivalent</li><li>print must be clear and easy to scan</li><li>laser or thermal printing is preferred</li><li>300 DPI is the recommended minimum</li></ul><h2>Products That Need Additional Labels</h2><ol><li><strong>Small items.</strong> Often need poly bags with suffocation warnings.</li><li><strong>Sharp items.</strong> Need protective packaging and safety labeling.</li><li><strong>Liquids.</strong> Must be protected against leaks, often with double-bagging.</li><li><strong>Hazmat products.</strong> Need specialized hazardous materials labeling.</li><li><strong>Expiration-dated products.</strong> Dates must remain visible.</li></ol><h2>Common Labeling Mistakes</h2><ul><li>using ASIN instead of FNSKU</li><li>leaving UPC or old barcodes visible</li><li>using labels that peel off in transit</li><li>applying wrinkled or crooked labels</li><li>leaving multiple scannable barcodes on the packaging</li><li>labeling bundles incorrectly</li></ul><h2>How a Prep Center Handles Labeling</h2><p>At SNS Prep Center, the labeling process is straightforward:</p><ol><li>receive and verify inventory</li><li>generate the correct FNSKU labels</li><li>apply labels to each unit</li><li>cover or remove old barcodes</li><li>quality-check each labeled item</li><li>pack inventory for Amazon shipment</li></ol><p>Pricing starts at $0.35 per unit including materials, with lower rates available at higher volumes.</p><h2>Final FBA Labeling Checklist</h2><p>Before sending inventory to Amazon, confirm that:</p><ul><li>every unit has the correct FNSKU label</li><li>labels are flat and readable</li><li>old barcodes are covered or removed</li><li>expiration dates remain visible</li><li>poly bags include suffocation warnings</li><li>case pack labels match the carton contents</li><li>labels are printed cleanly using laser or thermal methods</li></ul><p>If you want to avoid expensive labeling mistakes, it makes sense to hand the job to a prep center that deals with these rules every day.</p>