USPS Flat Rate Box Sizes help you send packages easily without worrying about weight or distance. If you want to ship something, knowing about USPS flat rate box sizes can save you time and money. With these boxes, you pay one price no matter where you send the package in the U.S. Many people use these boxes for sending gifts, documents, and even small products. They are good for home use, small businesses, and even online sellers. You can find different sizes that fit your needs, from small boxes to large ones. In this blog, we will explain everything in simple words. We will show you the types of flat rate boxes, their sizes, prices, and when to use each one. This guide is perfect for anyone who is new to shipping or just wants a clear and easy explanation. Let’s start learning about these helpful shipping boxes.
When you go to the post office or visit the USPS website, you will see many box options. But flat rate boxes are special. The reason people love USPS flat rate box sizes is because they offer a flat price—this means you don’t need to weigh your box or guess the cost. You just pick a box size, fill it up (as long as it closes properly), and pay the flat rate. It’s easy and stress-free! There are several box sizes available like Small Flat Rate Box, Medium Flat Rate Box (which comes in two shapes), and Large Flat Rate Box. USPS also offers a special APO/FPO Large Flat Rate Box for military and overseas shipping. This makes it easier for families and businesses to plan and send things without surprises in cost. In this article, we will break down each box size, how much it costs, what fits inside, and when it’s best to use it.
What Does USPS Flat Rate Mean
Flat rate means you pay one price for shipping, even if the box is heavy. The cost depends only on the size of the box — not the weight or where it’s going. This is perfect for sending things like gifts, clothes, or books.
USPS gives you the boxes for free. You can pick them up at your local post office or order them online. You just need to use the right size for what you’re shipping.
Why Use USPS Flat Rate Boxes
Here are some simple reasons people like USPS flat rate box sizes:
- No need to weigh your package.
- Easy to understand pricing.
- Boxes are free.
- You can track your package.
- Delivery is fast (usually in 1 to 3 business days).
Types of USPS Flat Rate Boxes
Let’s look at the different USPS flat rate box sizes. Each has its own shape and use. You can choose based on what you are sending.
1. Small Flat Rate Box
- Size: 8.69″ x 5.44″ x 1.75″
- Cost: Around $10.20 (check current USPS rates)
- Best For: Small items like jewelry, phone cases, or cables.
2. Medium Flat Rate Box (Top Loading)
- Size: 11.25″ x 8.75″ x 6″
- Cost: Around $17.10
- Best For: Clothes, toys, or books.
3. Medium Flat Rate Box (Side Loading)
- Size: 14″ x 12″ x 3.5″
- Cost: Same as top-loading box
- Best For: Flat items like board games, books, or electronics.
4. Large Flat Rate Box
- Size: 12.25″ x 12.25″ x 6″
- Cost: Around $22.80
- Best For: Bigger items, bulk clothing, or multiple things in one box.
5. APO/FPO/DPO Large Flat Rate Box (Military)
- Size: Same as large box
- Cost: Cheaper than regular large flat rate box
- Best For: Sending to military or U.S. territories.
Flat Rate Envelopes: Another Option
Flat rate envelopes are also available if your items are thin. They’re cheaper than boxes.
- Size: 12.5″ x 9.5″
- Cost: Around $9.90
- Best For: Documents, papers, thin books, or photos.
How to Choose the Right USPS Flat Rate Box Size
Picking the right box is simple:
- Small Flat Rate Box: For tiny or lightweight items.
- Medium Flat Rate Box: For medium-sized stuff like clothes or toys.
- Large Flat Rate Box: For big or many items.
- APO/FPO Box: For military shipping.
Where Can You Get USPS Flat Rate Boxes
You can get flat rate boxes:
- At your local USPS post office
- Online from the USPS website (they deliver free)
Tips to Save Money with Flat Rate Boxes
Here are smart tips:
- Use flat rate boxes for heavy items. If your box is light, other shipping may be cheaper.
- Always compare with Priority Mail or Ground Advantage.
- Reuse the original box if it’s still in good shape — but it must say “Flat Rate.”
- Don’t try to bend or cut the box to fit more. USPS won’t accept altered boxes.
Common Mistakes to Avoid
- Using a flat rate box for lightweight items (you might pay more).
- Overstuffing the box.
- Using tape to extend or reshape the box.
- Writing on the box outside of label space.
- Forgetting to check current shipping prices.
Conclusion
USPS flat rate box sizes make shipping easier for everyone. Whether you are sending a gift to a friend or running a small business, these boxes can save you time and remove the guesswork from shipping. You just pick a box size, pack your items, and pay one flat price. It’s simple, fast, and smart.
Now that you know how it works, you can choose the right box and start shipping with confidence. USPS flat rate boxes are a great tool — and when used correctly, they can save you money and make life easier.
FAQs
Q1: Can I use my own box for flat rate shipping?
No, you must use official USPS flat rate boxes to get the flat rate price.
Q2: Are USPS flat rate boxes really free?
Yes, the boxes are free. But you pay for shipping when you send them.
Q3: Is there a weight limit for flat rate boxes?
Yes. The limit is 70 pounds per box.