Poly mailers are lightweight, flexible, and cost-effective for shipping a variety of items. However, choosing the right size is crucial to ensure proper protection and avoid unnecessary shipping fees. In this guide, we’ll walk you through the correct way to measure a poly mailer, when to adjust for bulky items, and how to select the best size for your products.
Why Measuring Your Poly Mailer Correctly Matters
Picking the right poly mailer size affects:
✔ Product Protection: Items should fit securely without excessive empty space.
✔ Shipping Costs: Oversized mailers can increase shipping rates unnecessarily.
✔ Professional Presentation: A well-fitted package looks neat and professional.
✔ Ease of Sealing: A poly mailer that’s too small might not close properly.
Step-by-Step Guide to Measuring a Poly Mailer
1. Measure the Width (W)
- Lay the poly mailer flat on a table.
- Use a measuring tape or ruler to measure from one side to the other, excluding the side seams.
- This gives you the usable width of the mailer.
🔹 Example: If a poly mailer measures 12 inches across, the usable width is 12 inches.
2. Measure the Length (L)
- Measure from the bottom of the mailer to the top, excluding the flap.
- The flap is the adhesive strip that seals the mailer, so it should not be included in the length measurement.
🔹 Example: If a poly mailer is 19 inches long with a 2-inch adhesive flap, the usable length is 17 inches.
3. Consider the Flap Size
Most poly mailers come with a sticky sealing flap that is typically 1.5 to 2 inches long.
- If your item is thicker, the flap space may be reduced.
- Always leave extra room for sealing when choosing the right size.
4. Adjust for Thickness (D)
If your item is flat, width and length are enough.
However, for bulkier items like sweaters or shoes, you need to adjust the measurements to accommodate thickness:
Formula for Bulky Items
- New Width = Original Width + (Thickness × 2)
- New Length = Original Length + (Thickness × 1)
🔹 Example Calculation
You’re shipping a hoodie that measures:
- 11 inches wide
- 14 inches long
- 2 inches thick
📌 New Width = 11 + (2 × 2) = 15 inches
📌 New Length = 14 + (2 × 1) = 16 inches
💡 Best mailer size: 14.5″ x 19″ (allows sealing room).
Common Poly Mailer Sizes and Their Uses
| Item Type | Recommended Poly Mailer Size |
|---|---|
| T-Shirts (1-2) | 10″ x 13″ |
| Hoodies/Sweaters | 14.5″ x 19″ |
| Jeans/Pants | 12″ x 15.5″ |
| Small Accessories | 6″ x 9″ |
| Documents | 9″ x 12″ |
| Shoes (Boxed) | 19″ x 24″ |
| Soft Toys | 12″ x 15.5″ or larger |
| Bulkier Clothing | 14.5″ x 19″ or 19″ x 24″ |
Choosing the Right Poly Mailer Size: Key Considerations
✅ Flat vs. Bulky Items
- Flat items (T-shirts, documents, small accessories) can use a mailer just slightly larger than the item.
- Bulky items (sweaters, jackets, boxed items) need extra room to close properly.
✅ Padding & Protection
- Poly mailers don’t provide cushioning. If you’re shipping fragile or valuable items, use:
- Bubble wrap inside.
- Padded poly mailers instead.
- Boxes if additional protection is needed.
✅ Carrier Requirements
- Some shipping carriers charge extra fees for oversized or irregular-shaped packages.
- Check weight and dimensional pricing rules from USPS, UPS, FedEx, or DHL before choosing a size.
✅ Custom Branding
If you’re using custom printed poly mailers, ensure your design doesn’t get cut off when sealing.
- Leave at least 2 inches of clearance around key branding elements.
Mistakes to Avoid When Measuring Poly Mailers
❌ Choosing a size that’s too tight – Might not seal properly.
❌ Ignoring the thickness of the item – Can cause tearing or bulging.
❌ Not accounting for the adhesive flap – Reduces available space.
❌ Using a mailer too large – Increases shipping costs unnecessarily.
Frequently Asked Questions
Q: Can I use the same poly mailer size for different products?
Yes, but it depends on the items. A 14.5″ x 19″ mailer can fit hoodies, but might be too large for smaller accessories like jewelry. Consider having multiple sizes for different products.
Q: How do I measure a poly mailer for multiple items?
Stack the items together and measure the total width, length, and thickness. Use the bulky item formula to determine the correct mailer size.
Q: What’s the best way to store poly mailers?
Store them flat in a dry place to prevent warping. If they have an adhesive flap, avoid stacking heavy objects on top to prevent sticking.
Q: Do poly mailers have weight limits?
Yes, most poly mailers can hold up to 5-10 lbs, but always check the manufacturer’s weight rating.
Final Tips for Measuring Poly Mailers Like a Pro
📏 Measure the item’s width, length, and thickness accurately.
📦 Choose a slightly larger size to allow space for sealing.
💡 Use the thickness formula to adjust for bulky items.
🚀 Double-check shipping carrier size and weight requirements.
🔄 Keep different sizes on hand for different products.
By following these simple steps, you’ll save money, prevent damage, and ensure hassle-free shipping with the perfect poly mailer size every time! 🚀📦
Find the Perfect Poly Mailer for Your Needs
Choosing the right poly mailer is essential for secure and cost-effective shipping. At Plus Packaging, we provide a wide selection of high-quality poly mailers designed to protect your products while keeping shipping costs low. Whether you need custom-branded mailers or durable standard options, we’ve got you covered. Explore our collection and find the perfect poly mailer for your business.