Why Your Barcodes Keep Failing

The first thing you need to do is determine whether the barcode will be visible through the polybag or placed on the exterior. A barcode may be readable through the bag, but glare, loosely wrapped film, and other packaging issues can interfere with scanning. Therefore, always test the packaging before use, as you never know how the scanner will respond.

If your scanner cannot reliably read the barcode because of these issues, affix an identical barcode to the outside of the polybag. This provides a clearer scanning surface and helps reduce errors during order processing.

Next, position the barcode on a flat portion of the bag. Never place it over a fold, corner, seam, zipper, or curved surface. When the package is moved during normal handling, the barcode's black lines should remain straight and undistorted. For example, placing a stiff card inside the bag can help keep labels smooth when attaching them to soft products.

You should also leave enough space around the barcode to prevent words, borders, pictures, tape, or other printed elements from touching its edges. Scanners need adequate clear space on both sides of the barcode to identify where the code begins and ends. If you cut a label too close to the barcode, you may eliminate this essential space when trimming the edges.

Shiny plastic can create scanning problems because reflected light interferes with barcode recognition. In such cases, applying a suitable clear paper label to the outside of the bag can provide a better scanning surface. Make sure the adhesive is compatible with the polybag material. A label with a lifted corner can become distorted during shipment or detach completely, making the barcode difficult to scan.

Print quality is just as important as barcode placement. Faded printing, broken lines, smudges, misalignment, and registration errors can all lead to missed scans. Before producing hundreds of labels, print a small sample and test the results. If you notice faint stripes or other printing defects, replace worn supplies and clean the printer as needed.

Another important consideration is multi-product polybags. These bags may contain several items, each with its own barcode. Displaying multiple barcodes can confuse scanners and cause inventory or order-picking errors. Some warehouses require a single barcode to represent all the items in a polybag, while others require individual barcodes to be covered or concealed. Before preparing your shipment, confirm the specific requirements of your client, carrier, or third-party logistics (3PL) provider.

Barcode testing should replicate actual warehouse conditions as closely as possible. Fill and seal the polybags, then scan them from different angles using a scanner similar to the equipment employees use. Gently rub the labels, stack packages on top of one another, and scan them again after allowing some time to pass. If a barcode scans successfully only when the bag is wrapped tightly or positioned at a precise angle, it is not ready for warehouse use.

Finally, display an example of a correctly positioned barcode label near your packing station so employees can follow a consistent standard. You can also provide each employee with a reference card explaining which barcode to use, where to place it, and which existing barcodes must be hidden when applicable. Following clear barcode labeling procedures helps prevent shipping delays, incorrect product selections, and unnecessary relabeling. Ultimately, proper barcode placement and testing help ensure that customers receive the products they ordered efficiently and without avoidable handling issues.