How to Use Poly Mailers for E-commerce: Best Practices

Overview

Poly mailers are a go-to packaging choice for many e-commerce businesses because they combine affordability with ease of use. This guide explains step-by-step best practices for selecting, packing, sealing, and labeling poly mailers so you can ship efficiently while protecting your products and brand reputation.

Select the right mailer

Choosing the correct mailer starts with product assessment. Measure the product dimensions and choose a mailer that allows for minimal extra space—too much empty volume can lead to shifting and damage. For items that could be scratched or slightly impacted, opt for bubble-lined poly mailers. For everyday apparel, standard LDPE mailers are usually sufficient.

Packing steps

Follow these straightforward packing steps to reduce damage and returns:

1. Prepare the item: Fold clothing neatly, remove tags if needed, and place fragile accessories in small protective sleeves.
2. Add internal protection: Use tissue paper, poly bags, or small bubble wrap pieces for extra protection and brand presentation.
3. Insert into the mailer: Slide the product in with minimal force; avoid overfilling which can stress seams and adhesive strips.
4. Seal properly: Remove the adhesive liner and press the flap firmly along the entire width. For heavy or high-value items, reinforce with shipping tape across the seal.
5. Label accurately: Affix the shipping label flat and ensure barcodes are unobstructed. Include a packing slip inside or a return label if space permits.

Branding and presentation

Poly mailers can serve as a brand touchpoint. Consider using printed mailers with your logo or a distinctive color. However, balance the cost of custom printing against the volume of shipments and expected return on investment. For a professional unboxing, include a printed packing slip, care instructions, or a small thank-you card.

Weight and dimensional considerations

Carriers calculate shipping charges based on actual weight and sometimes dimensional (DIM) weight. Because poly mailers are lighter and take less volume than boxes, they often reduce postage costs—especially valuable for soft, compressible items. Always verify carrier-specific DIM policies when choosing mailer sizes.

Security and tamper-evidence

Standard poly mailers are easy to seal but also easy to open. For higher-value items, consider tamper-evident or security seals and document the packaging condition before shipping (photos can help resolve disputes). Keep a record of the tracking number and expected delivery date to monitor shipments.

Handling returns

Include return instructions and, if practical, a prepaid return label inside the package or as a readily accessible printed insert. Clear return processes reduce customer friction and expedite restocking. For easy restocking, request returned items to be in sellable condition and consider a short inspection checklist for returned inventory.

Storage and inventory considerations

Store poly mailers flat in a dry area to prevent warping or dust accumulation. Protect adhesive strips from heat and high humidity to preserve seal integrity. If using multiple sizes and types, organize them in labeled bins or racks near packing stations to minimize picker errors and speed fulfillment.

Automation and integration

If you operate at scale, integrate poly mailer dimensions into your WMS so packing guidelines appear at the packing station based on SKU. Use barcode scanning to confirm correct mailer selection and print shipping labels automatically with compatible software. Automation reduces human error and speeds order throughput.

Cost control and purchasing tips

Buy in bulk to lower per-unit cost; negotiate with suppliers for volume discounts. Compare single-layer vs. bubble-lined costs—reserve the more expensive option for items that need it. Monitor damage rates and returns to determine if additional protection is financially justified.

Common mistakes and how to avoid them

Beginners frequently encounter a few recurring problems:

• Incorrect sizing: Using oversized mailers increases shipping cost and movement inside the package—measure and standardize sizes.
• Poor sealing: Failure to fully press down adhesive strips or rely solely on the adhesive for heavy items—reinforce with tape if necessary.
• Inadequate protection: Shipping hardware, shoes, or electronics in bare poly mailers leads to damage—use boxes or padded mailers for those categories.
• Ignoring carrier rules: Some carriers have restrictions on materials or require special labeling—check carrier guidelines before shipping at scale.

Real-world examples

A subscription T-shirt brand standardized on five poly mailer sizes and integrated size selection into the order-picking workflow, reducing packing time by 30% and lower postage costs by 18% year-over-year. A boutique selling handmade scarves switched to bubble-lined poly mailers for certain SKUs after a spike in returns; damage-related returns dropped by half.

Final tips



Test packaging choices with a small batch before committing to a particular mailer type. Track damage and return data to inform future packaging decisions. For many e-commerce businesses, poly mailers provide an excellent balance of cost, convenience, and brand presentation when used thoughtfully.