Guide to USPS Flat Rate Shipping, Boxes & Envelopes

As an eCommerce store owner, you've probably been looking for affordable and convenient shipping options. We're going to go out on a limb and say that you've come across flat rate shipping as an option and that it may sound appealing for your business.

You might have read that this shipping option saves a lot of money, but before you take that leap, it's best to understand what this shipping option is all about.

In this post, we'll discuss what flat rate shipping means and the variety of services that the United States Postal Service (USPS) offers if you're interested in moving forward with this option.

What is USPS Flat Rate Shipping?

Flat rate shipping is a shipping service that you can find offered by a variety of couriers, notably USPS. Its major feature is that it charges one flat rate regardless of the weight of the package.

If you're shipping very heavy items and it happens to be able to fit within the various packaging options provided, this could potentially save you money on shipping costs.

How Does it Work?

USPS offers different box sizes and envelope types, all with different pricing. As long as your item fits within the packaging and it is below the weight limit, you only have to pay that specified price - making the calculation of your flat rate shipping costs easier.

USPS Flat Rate Shipping Delivery Times

For domestic service, the delivery timeframe is usually between 1 to 3 business days. With the USPS international flat-rate service, the delivery timeframe is quoted as 6 to 10 business days.

Does USPS Flat Rate Include International?

It sure does! You can ship to more than 190 countries for USPS flat rate international shipping. For a complete list, visit USPS' Index of Countries and Localities for more information and potential restrictions for your destination country.

Additionally, with domestic flat rate boxes, you can ship packages to any location within the United States.

How Much Does USPS Flat Shipping Cost?

Here are some popular USPS flat rate envelope and box sizes, and their pricing in 2023:

Related Post: USPS 2023 Shipping Rate Changes

How Does it Compare with Other Services?

UPS and FedEx each have their own flat-rate services as well that offer comparable rates to USPS. The rate for a Small FedEx Flat Rate Box measuring 8 3/4" x 2 5/8” x 11 1/4" starts at $8.65 while the Medium Box measuring 8 3/4" x 4 3/8” x 11 1/4" starts at a rate of $11.20. UPS Simple Rate starts at $10.25 for a small package and goes up to $16.75 for a large package.

USPS Flat Rate Boxes and Envelopes

Many businesses like using USPS' flat-rate service because the boxes and envelopes are provided free of charge. Also, worth noting is that the shipping label must match the box you already have.

Apart from being under the weight limit, it is also important that the content of a given box or envelope fits inside properly, without requiring any modifications to the packaging, such as altering the folds.

Benefits of Using USPS Flat Rate Shipping in eCommerce

USPS flat rate shipping is a popular option for eCommerce merchants as it simplifies shipping costs and offers free packaging. This allows merchants to offer free shipping or reduced costs back to their customers. This is particularly beneficial for stores that ship small but heavy items. However, they will need to fall under the weight maximum.

While the free supplies and pricing relative to weight may make flat rate shipping seem alluring, it may not be the best solution for the following reason:

• Pricing is not as transparent

Some customers like to see a complete breakdown of shipping costs, and it's hard to show them with a flat rate. It also doesn't provide adequate information on duties and taxes, making it difficult for overseas customers to determine if additional fees could be added.

It may cause you to overspend on shipping if you're not careful

To determine whether you're actually saving money on shipping, you'll need to know at what weight and which distance the flat rate becomes competitive. With the multiple variables involved to calculate this, it can be really hard to keep track of.

However, Easyship now offers USPS flat rate shipping options on our platform, and when used with our algorithm, you can efficiently ensure that flat rates only apply to qualified shipments as they are being processed! Learn more.

Important Restrictions to Know

There are definitely restrictions on what items can be shipped. You can't ship ammunition, gasoline, airbags, explosives, cigarettes, marijuana, and any other form of tobacco in flat rate boxes.

For flat rate shipping domestically within the US, the maximum weight approved for each package or envelope is 70 lbs.

For USPS international flat rates, the maximum weight for Priority Mail International Flat Rate Envelopes and Small Flat Rate Priced Boxes is 4 lbs. Additionally, the maximum weight for medium and large Priority Mail International Flat Rate Boxes is 20 lbs.

It's also worth noting that some countries may have lower weight restrictions.

What about Shipping Labels?

You will need to purchase shipping labels that match the specific flat rate box that you are purchasing. For example, if you are using a small flat rate box, you will need to purchase the corresponding flat rate box label.

How to Use USPS Flat Rate Shipping Boxes with Easyship

You can easily use USPS flat rates shipping boxes with Easyship. To do this you need to go to the boxes section in your dashboard and activate the boxes that you want to use. You can choose to have them automatically selected or done manually. For further instruction, you can visit our help center.

Is Flat Rate Shipping Right for Your Business Needs?

While flat rate shipping sounds good in theory, it's best to analyze your business' shipping needs and costs to ensure you do not overspend on shipping.

As a best practice, we suggest providing at least 2 options at checkout that show calculated rates, so customers can readily see if it's best to use the flat rate option (or choose a faster delivery option if needed).

For more information about how to offer this option for your store, install our Rates at Checkout feature – it's free!

USPS Flat Rate Shipping FAQ

Does Flat Rate shipping include tracking?

Yes. Tracking is among the few eCommerce shipping essentials. As such, all common couriers include tracking with all shipping services.

What can't be shipped with Flat Rate shipping?

Couriers restrict the shipment of several items, regardless of the shipping method. These items include firearms, gasoline, airbags, explosives, and alcohol. Otherwise, the only restriction to Flat Rate shipping is that the package cannot exceed 50-70 pounds in weight, courier depending.

Where can I purchase Flat Rate boxes?

You can order Flat Rate boxes from the websites of your chosen courier, including USPS, FedEx, and UPS. Unlike most shipments that allow you to use any box, Flat Rate shipments must use a Flat Rate box. This is because the box itself serves as the postage.

Is insurance included with Flat Rate shipping?

Couriers provide limited insurance with all shipments, and Flat Rate is no exception. USPS, for instance, provides automatic shipping insurance up to $50. For additional coverage, you'll need to purchase insurance when you buy your shipping label.

Is there a weight limit?

Yes. Different couriers have weight restrictions for Flat Rate shipments. USPS has a limit of 70 pounds, while FedEx and UPS both cap Flat Rate packages at 50 pounds.

Can I use my own box for Flat Rate shipping?

Only if you are shipping with UPS. If you’re going with USPS or FedEx, you must purchase boxes from the company.