2021 USPS First-Class Shipping Rates Changes

By Rob Zaleski
Jan 28, 2020
2019 First Class shipping rates

The rates in this blog are the 2021 USPS shipping rates. For the current 2023 USPS rates, visit our USPS 2023 Shipping Rate Changes: Flat Rate, Priority, First Class, w/Tables blog!

As of July 9, 2023, Retail Ground, Parcel Select, and domestic First-Class Package Service will be combined into USPS Ground Advantage™. Visit our blog for more information!

In this article, we break down all the 2021 First-Class shipping rates using USPS Commercial Rates, which sellers can get through a shipping software like ShippingEasy. We’ve also provided a full breakdown of 2021 USPS shipping rate changes here.

One of the most significant changes back in 2019’s USPS shipping rates changes was an overhaul of how First-Class shipping rates were calculated. What has typically been the most economical means of shipping packages under 1 lb. saw an average cost increase of 11.9%. This is predominantly due to transitioning from a flat cost regardless of domestic destination to Zone-based tiers, the way Priority Mail has been calculated.

Learn more about USPS zones with our blog!

We wrote a breakdown of how this played out in 2019, and exactly what it meant for online sellers who ship using First-Class Package Service. But here, we will cover everything that changed in 2021 for USPS First-Class Package service shipping rates.

Note: As of October 19, 2022, ShippingEasy now offers the lowest USPSⓇ shipping rates in the industry, and the rates reflected in this blog are prior to this change and may not be accurate. For more information on these new rates, check out our blog!

How are the 2021 First-Class Shipping Rates Calculated?

First-Class Package Service from USPS is (still) the most cost-effective shipping method for packages weighing less than 1 lb. You can use your own boxes or padded envelopes. Before the 2019 overhaul, all you needed to know was the weight of your package, and you were able to ship anywhere domestically at a relatively inexpensive cost, particularly compared to other methods.

Let your software choose when to use the right shipping service and carrier. Start your 30-day free trial of ShippingEasy and ship first-class mail faster for less!

With the 2019 changes to USPS First-Class shipping rates, the destination was taken into account, and it changed the postage costs in a big way. We’ve updated our charts to show you the 2021 First-Class package rates based on the most current model that USPS uses.

2021 USPS
First Class Pkg
(weight not over)
1 & 2
1 oz$3.01$3.03$3.06$3.12$3.22$3.35$3.49$3.49
2 oz$3.01$3.03$3.06$3.12$3.22$3.35$3.49$3.49
3 oz$3.01$3.03$3.06$3.12$3.22$3.35$3.49$3.49
4 oz$3.01$3.03$3.06$3.12$3.22$3.35$3.49$3.49
5 oz$3.46$3.49$3.51$3.57$3.58$3.69$3.85$3.85
6 oz$3.46$3.49$3.51$3.57$3.58$3.69$3.85$3.85
7 oz$3.46$3.49$3.51$3.57$3.58$3.69$3.85$3.85
8 oz$3.46$3.49$3.51$3.57$3.58$3.69$3.85$3.85
9 oz$4.04$4.09$4.12$4.20$4.38$4.53$4.68$4.68
10 oz$4.04$4.09$4.12$4.20$4.38$4.53$4.68$4.68
11 oz$4.04$4.09$4.12$4.20$4.38$4.53$4.68$4.68
12 oz$4.04$4.09$4.12$4.20$4.38$4.53$4.68$4.68
13 oz$5.19$5.23$5.27$5.42$5.66$5.81$5.98$5.98
14 oz$5.19$5.23$5.27$5.42$5.66$5.81$5.98$5.98
15 oz$5.19$5.23$5.27$5.42$5.66$5.81$5.98$5.98
15.999 oz$5.19$5.23$5.27$5.42$5.66$5.81$5.98$5.98

Let’s take a look at a couple of specific examples to show how much 2021 USPS First-Class package shipping rates have increased. As a percentage on a whole, First-Class Package rates saw the largest increase over last year’s rates:


  • 2020 USPS First-Class Package
    • 6 oz. package, Houston to Miami = $3.31
  • 2021 USPS First-Class Package
    • 6 oz. package, Houston to Miami (Zone 5) = $3.57 (+ $0.26)
  • 2020 USPS First-Class Package
    • 11 oz. package, New York to Los Angeles = $4.46
  • 2021 USPS First-Class Package
    • 11 oz. package, New York to Los Angeles (Zone 8) = $4.68 (+ $0.22)

If you are an online seller with a predominantly local customer base, you may not notice the changes to your shipping costs significantly. However, those who ship across the country and/or have packages close to the 15.999 oz. weight limit on a regular basis will need to budget in higher shipping costs for 2021, which could represent a burden.

Need to know: How to ship liquids with each carrier.

What about First-Class shipping rates for international?

First-class shipping rates are increasing for international shipping, but are seeing a structural change as well. In years past, First-Class Package International Service (FCPIS) was split up into 9 Price Groups. In 2021, FCPIS is now split into 20 different Price Groups.

The shipping costs do represent a significant jump over last year which will certainly impact smaller vendors who do a substantial amount of shipping light packages overseas.

Due to the extension of groups to 20, we are not providing a chart of the 2021 First-Class Package International Service rates.

This rate change is certainly something that merchants who ship internationally will have to adjust for.

Learn more about USPS International Shipping Options!

Find out if international shipping is right for your business and how to ensure your international shipping labels meets all of the requirements once you decide to incorporate this feature.

What does this mean for e-commerce shippers in 2021?

Even with these increases in this mail class, First-Class Package Service is still going to be the most cost-effective shipping option for lighweight packages under 1 lb. Online sellers are going to have to make adjustments, particularly if you currently offer free shipping and just absorb the cost.

The 2021 USPS First Class Package service shipping rate changes took effect on January 27, 2021. If you haven’t read our complete wrap-up of the major changes to USPS shipping rates in 2021, click the button below to learn everything you need to know about changes coming to Priority Mail, overall rate change highlights, and a refresher on Dimensional Weight (DIM weight) structures.

Learn More

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Rob Zaleski

Head of Brand at ShippingEasy
I'm a digital content and social media nerd with a passion for telling stories, helping connect people, and finding joy in the details.

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