Poly mailers are lightweight plastic mailing bags designed to ship non-fragile products like clothing, books, and accessories at lower cost than cardboard boxes. Made from durable polyethylene or polypropylene, these self-sealing bags protect products from moisture and tampering while reducing shipping expenses.
Plus Packaging has been manufacturing packaging materials for nearly 50 years. We’ve worked with thousands of businesses choosing between poly mailers and boxes for their products. This guide explains what poly mailers are, when to use them, the types available, and where to get them.
What Are Poly Mailers?
Poly mailers are flexible plastic shipping envelopes made from polyethylene or polypropylene film. They’re designed for mailing products that don’t require rigid box protection.
Key features:
- Self-sealing adhesive strip (no tape needed)
- Moisture-resistant plastic film
- Lightweight construction (1-3 ounces)
- Available in sizes from 6×9 to 19×24 inches
- Shipping labels stick directly to surface
- Tamper-evident seal
The plastic film typically measures 2 to 3 mils thick, providing tear resistance while keeping weight minimal. Custom poly mailers can include your logo and branding printed directly on the bag.
Poly Mailers vs Boxes: Why Use Poly Mailers?
Significantly Lower Shipping Costs
Dimensional weight savings: Poly mailers are flat, essentially eliminating dimensional weight charges. Boxes add height that increases dimensional weight calculations.
Material costs: Poly mailers cost $0.10 to $0.60 per unit. Comparable boxes cost $0.50 to $2.00 or more.
Weight difference: A poly mailer weighs 1-3 ounces. An equivalent box weighs 6-12 ounces before adding products.
Practical Advantages
No tape needed: Self-sealing adhesive saves time and eliminates tape costs.
Compact storage: 100 poly mailers take up a fraction of the space that 100 flat boxes require.
Mailbox delivery: Small poly mailers sometimes fit in mailboxes, reducing porch theft risk.
Moisture protection: Water-resistant plastic protects contents from rain and humidity better than cardboard.
Custom Branding
Print your logo, brand colors, and graphics directly on poly mailers. Custom printing turns functional packaging into marketing materials customers see when packages arrive.
Eco-Friendly Options
Recyclable poly mailers, compostable mailers, and options made from recycled materials address environmental concerns while maintaining performance.
When Boxes Are Better
Use boxes instead of poly mailers for:
- Fragile items that can break
- Glass products
- Multiple items that need separation
- Products requiring premium presentation
- Items that can be crushed
Which Products Can Be Shipped with Poly Mailers?
Poly mailers work for products that pass this test: “Will this survive being thrown in a pile with heavy boxes on top?”
Best Products for Poly Mailers
Apparel and clothing: T-shirts, jeans, hoodies, socks, athletic wear, underwear. Clothing can’t be crushed like fragile items. Avoid using poly mailers for dresses with intricate beading or delicate ornaments.
Fabric-based products: Bedding, sheet sets, towels, fabric swatches, yarn, face masks. Any soft fabric items work well.
Books and printed media: Books, magazines, catalogs, printed materials. Books are already sturdy. Bubble-lined poly mailers provide extra protection for book corners.
Products in sturdy packaging: Items already packaged in hard materials don’t need boxes. Examples include playing cards, phone cases, small board games, and shoes in their original boxes.
Health and beauty products: Vitamins, supplements, cosmetics like mascara or lipstick tubes. Only if products are sealed tight and won’t break when dropped. Skip poly mailers for liquids in glass or products that could leak.
Soft, flat items: Anything that won’t crush, break, or get damaged from pressure during shipping.
Products That Need Boxes
Don’t use poly mailers for:
- Fragile items (sunglasses, ceramics, delicate jewelry)
- Glass products
- Crushable foods (chips, crackers, cookies)
- Multiple items that might scratch each other
- Items requiring structure to maintain shape
- Premium products where box presentation matters
Types of Poly Mailers
Different poly mailer types serve different needs. Choose based on your product protection requirements and brand values.
Standard Poly Mailers
Basic white or gray plastic bags with no padding. The most cost-effective option at $0.10 to $0.25 per unit. Best for durable items like t-shirts, jeans, and products that don’t need cushioning.
Bubble Mailers
Poly mailers with bubble wrap padding on the interior. Costs $0.25 to $0.50 per unit. Provides extra protection for products that could get scratched or dented. Good for books, cosmetics, small electronics, and clothing with ornaments.
Compostable Poly Mailers
Made from plant-based materials that break down in compost. Costs $0.40 to $0.60 per unit. Appeals to eco-conscious customers and aligns with sustainable brand values. Performance matches standard poly mailers.
Recycled Poly Mailers
Made with 50% to 100% recycled plastic materials. Costs $0.20 to $0.40 per unit. Durable and moisture-resistant like standard options but with lower environmental impact.
Expansion Poly Mailers
Heavy-duty mailers with padded bottoms and gusseted sides. Costs $0.35 to $0.55 per unit. Designed for bulkier items like thick books, binders, jackets, and sweatshirts. More tear-resistant than standard options.
Clearview Poly Mailers
Transparent front panel shows product inside. Costs $0.30 to $0.45 per unit. Good for displaying products like books, magazines, or printed materials. Branding and shipping labels go on the opaque back.
Tyvek Poly Mailers
Made from densely woven polyethylene fibers. Costs $0.40 to $0.70 per unit. Extra durable and water-resistant. Used for important documents, photographs, and items needing maximum protection.
How Much Do Poly Mailers Cost?
Poly mailer costs vary by type, size, and order quantity. Here are typical price ranges:
By type:
- Standard poly mailers: $0.10 to $0.25 per unit
- Bubble mailers: $0.25 to $0.50 per unit
- Compostable mailers: $0.40 to $0.60 per unit
- Recycled mailers: $0.20 to $0.40 per unit
- Expansion mailers: $0.35 to $0.55 per unit
- Tyvek mailers: $0.40 to $0.70 per unit
By size:
- Small (6×9): $0.10 to $0.20
- Medium (10×13): $0.15 to $0.30
- Large (14×19): $0.25 to $0.45
- Extra large (19×24): $0.35 to $0.60
Bulk pricing: Ordering 1,000+ units typically reduces per-unit cost by 20% to 40%. Ordering 5,000+ units offers even better pricing.
Cost comparison to boxes: A poly mailer costs $0.15 to $0.40 for most common sizes. An equivalent cardboard box costs $0.50 to $2.00. The poly mailer saves $0.35 to $1.60 per shipment on materials alone.
Total shipping savings: Combine material savings with reduced dimensional weight charges. Most businesses save $1 to $3 per shipment using poly mailers instead of boxes for appropriate products.
Poly Mailer Sizes and How to Choose
Choose poly mailer size based on your product dimensions when laid flat. The mailer should fit the product comfortably without excessive extra space.
Common Sizes and Products
6×9 inches: Small accessories, socks, phone cases, jewelry, small cosmetics
10×13 inches: T-shirts, tank tops, small books, fabric (1 yard), face masks
12×15 inches: Multiple t-shirts, jeans, sweaters, medium books, fabric (2 yards)
14×19 inches: Large sweaters, hoodies, thick books, fabric (3 yards), multiple clothing items
19×24 inches: Bedding, sheet sets, winter coats, bulky items, large fabric orders
How to Measure
- Lay your product flat
- Measure length and width at widest points
- Add 1-2 inches to each dimension for easy fit
- Round up to nearest standard size
Too small causes problems: If the poly mailer doesn’t fit properly, it can get caught in postal processing machines, causing tears and damage.
Too large wastes money: Excess space means you’re paying for material and shipping weight you don’t need.
Where to Get Poly Mailers
Plus Packaging
We manufacture poly mailing bags in standard and custom sizes. Our 50 years of experience means we can help you choose the right type and size for your products. We offer custom printing, eco-friendly options, and flexible minimum quantities.
Retail Locations
USPS: Available at post offices and online. Sometimes offers free poly mailers for Priority Mail shipments.
FedEx and UPS: Available at retail locations and online stores.
Walmart and Target: Stock basic poly mailers in stores and online.
Online Suppliers
Many packaging suppliers sell poly mailers online with delivery to your location. Compare pricing, minimum quantities, and shipping costs when choosing suppliers.
Custom vs Stock
Stock poly mailers: Plain white or gray bags available immediately. Lower cost but no branding.
Custom poly mailers: Printed with your logo and branding. Require minimum order quantities (typically 500-1,000 units) and 2-4 week production time.
Pros and Cons of Poly Mailers
Pros
Lower shipping costs: Reduced dimensional weight and lighter packages save $1 to $3 per shipment compared to boxes.
Cheaper materials: Cost $0.10 to $0.60 per unit versus $0.50 to $2.00+ for boxes.
No tape needed: Self-sealing adhesive saves time and eliminates tape costs.
Moisture resistant: Plastic protects contents from rain and humidity better than cardboard.
Compact storage: Take up minimal warehouse or storage space.
Custom branding available: Print logos and graphics directly on mailers.
Eco-friendly options: Compostable and recycled versions available.
Mailbox delivery: Small mailers sometimes fit in mailboxes, reducing theft risk.
Cons
Not for fragile items: Won’t protect glass, ceramics, or easily breakable products.
Limited for multiple items: Not ideal for shipping several items together unless they’re all soft.
Can tear if wrong size: Overstuffed mailers risk tearing during handling.
Less premium presentation: Don’t create the same unboxing experience as nice boxes.
Not suitable for all products: Many items still require box protection.
Frequently Asked Questions
What is a poly mailer used for?
Poly mailers are used for shipping non-fragile products like clothing, books, accessories, and items in sturdy packaging. They protect products from moisture and tampering while reducing shipping costs compared to boxes.
Are poly mailers cheaper than boxes?
Yes, poly mailers cost $0.10 to $0.60 per unit compared to $0.50 to $2.00+ for boxes. They also reduce shipping costs through lower dimensional weight. Most businesses save $1 to $3 per shipment using poly mailers instead of boxes.
Can you ship shoes in poly mailers?
Yes, shoes work well in poly mailers because they’re typically already packaged in sturdy shoe boxes. The poly mailer protects the shoe box from moisture during shipping without adding unnecessary bulk.
What size poly mailer do I need?
Measure your product laid flat, add 1-2 inches to each dimension, then round up to the nearest standard size. Common sizes: 6×9 for small items, 10×13 for t-shirts, 12×15 for jeans or sweaters, 14×19 for hoodies, and 19×24 for bedding.
Are poly mailers waterproof?
Poly mailers are water-resistant, not fully waterproof. They protect contents from rain and humidity during normal shipping conditions but won’t keep water out if submerged or exposed to heavy water pressure.
Can poly mailers be recycled?
Standard poly mailers can often be recycled with plastic bags at grocery store drop-off locations, not in curbside recycling. Compostable poly mailers break down in compost facilities. Recycled poly mailers are made from recycled materials.
Do I need tape to seal poly mailers?
No, poly mailers have self-sealing adhesive strips. Peel the protective liner and fold the flap down to create a secure, tamper-evident seal. No tape required.
Where can I buy poly mailers in bulk?
Buy poly mailers in bulk from packaging manufacturers like Plus Packaging, online suppliers, or shipping carriers. Bulk orders of 1,000+ units typically offer 20% to 40% cost savings compared to small quantities.
Can poly mailers be customized?
Yes, poly mailers can be custom printed with your logo, brand colors, and graphics. Custom printing requires minimum quantities (typically 500-1,000 units) and 2-4 week production time.
What’s the difference between poly mailers and bubble mailers?
Poly mailers are thin plastic bags. Bubble mailers have bubble wrap padding on the interior for extra protection. Bubble mailers cost more ($0.25 to $0.50 vs $0.10 to $0.25) but protect products from scratches and dents.
Conclusion
Poly mailers are lightweight plastic shipping bags that reduce costs and protect non-fragile products during transit. They work best for clothing, books, fabric items, and products already in sturdy packaging.
The main advantages are lower shipping costs (through reduced dimensional weight), cheaper materials, moisture protection, and self-sealing convenience. Poly mailers cost $0.10 to $0.60 per unit and can save $1 to $3 per shipment compared to boxes.
Choose poly mailers when products can withstand pressure during shipping. Use boxes for fragile items, glass products, or anything that can be crushed.
At Plus Packaging, we manufacture poly mailing bags in standard and custom sizes. Our team can help you choose the right type and size for your products based on 50 years of packaging experience. Contact us to discuss your poly mailer needs.