Key Points:

  • USPS commercial parcels must measure at least 3 inches high x 6 inches long x 1/4 inch thick
  • USPS First Class Package and USPS Priority Mail Flat Rate Small can help you ship your small packages, though restrictions apply
  • Easyship saves users up to 91% off discounted shipping rates for all USPS shipments

Whenever you’re shipping a package, it’s essential to understand the shipping rules and regulations so that there are no surprises, which is why it’s vital to comprehend USPS's minimum and maximum weight requirements.

Ultimately, understanding USPS's minimum and maximum package dimensions will help save you from paying excess fees when you can just pay for the correct shipping size.

This blog post will cover everything you need to know about the minimum package size to ship with USPS, so you can better understand the best practices to ship small or large packages with USPS.

Table of Contents

What is the Smallest Package USPS Will Ship?

According to USPS, the minimum package size is at least 6 inches in length, 3 inches in height, 1/4 of an inch in thickness, or 6 x 3 x 0.25. This regulation means that the size and height of your package box should be at least 6 inches in length and 3 inches in height.

USPS Small Package

USPS First Class Package and USPS Priority Mail Flat Rate Small can help you ship your small packages. Both services deliver in 1-3 business days with free tracking. With USPS, prices start at $4.50 for USPS First Class, while Priority Mail starts at $8.70 for shipments.

Is there a maximum size for shipments?

Packages cannot weigh more than 70 pounds and cannot be 108 inches in length and girth. For USPS Retail Ground, the maximum is 130 inches, and for USPS First Class Mail, it is 15.99 oz for small package sizes USPS.

Related post: The Ultimate Guide for USPS Boxes

How to Mail a Small Package with USPS

Shipping a USPS small package doesn’t have to be a hassle, that’s why we’ll give you the full play-by-play when it comes to USPS small package sizes.

We’ll go over the best practices for shipping with USPS here.

Get a free small USPS box

First, obtain a small USPS box for your shipment. You can get these online for free on the USPS website or obtain them from your local post office. There is no additional charge for flat rate boxes and flat rate envelopes.

Pack your items and seal your box

Ensuring that your box arrives intact is very important. First, ensure that your package is packed correctly and layered with enough cushioning and packaging materials. This step is even more critical if you're shipping fragile items. Also, seal your box correctly by taping every side of it, ensuring its safety.

Ship your USPS small package

If you have followed the steps above, the next step is to prepare to ship. After that, you can arrange for free package pickup or drop off your packages at the local post office.

Fortunately, Easyship saves users up to 91% off discounted rates for USPS shipments. So instead of paying retail rates, you can get instant access to high-volume discounts. Plus, Easyship offers premium shipping tools and extra services every eCommerce merchant can enjoy.

How Much Does It Cost to Ship a USPS Small Package?

Whenever you’re shipping a parcel, there are factors you should consider. No matter what, the following factors determine the cost of shipping:

  • Courier service
  • Delivery speed
  • Weight of package
  • Shipping distance
  • Package dimensions

This section will go through the cost of shipping small packages from USPS courier services and compare them with Easyship’s discounted shipping rates.

USPS First Class Package Cost

Let's say you’re shipping a lightweight package that weighs 0.5 pounds from New York to Los Angeles, we’ll compare how much it costs to ship with USPS retail rates.

Easyship costs $4.15 to ship the same package, which means you can save $1.35 when using our shipping platform.

Our Shipping Rates Calculator offers the best available rates for all eCommerce merchants, plus our team of shipping experts can help you every step of the way.

USPS Priority Mail Flat Rate Small

Say you’re shipping the same lightweight package from New York to Los Angeles, here’s how much it costs to ship USPS Flat Rate with USPS retail rates.

Alternatively, Easyship helps you save $1.20 with our competitive pricing. You’ll only pay $8.25 to ship the same package with USPS Flat Rate – making Easyship the clear-cut winner.

Shipping USPS Small Packages with Easyship

Shipping small packages is impossible when you don't have the correct information. USPS is known to have strict guidelines for the sizes of packages. There is a minimum acceptable size, just as there is a maximum size for parcels.

Understanding packaging dimensions are essential, especially if you don’t want to pay oversize or large package fees. With Easyship's helpful features, you get to worry less about the stress of shipping, even if you're shipping certified mail or diplomatic mail.

In addition, you’ll gain instant access to premium shipping features, such as the following:

  • Shipping Rates Calculator: Access high-volume discounts from 250+ couriers. Plus, get instant access to delivery lead times from premium shipping couriers
  • Easyship Branding Suite: Easyship helps your business provide visibility from checkout to delivery with automated messages, dedicated tracking pages, and branded tracking features
  • Shipping Policy Generator: Our shipping policy generator helps merchants and crowdfunding campaigns generate their shipping policy by providing tracking and insurance options, plus other vital information for your shipping process

Ready to ship? Sign up for a FREE Easyship account and learn how to save instantly on USPS First Class shipping


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