Key Points:

  • First-class mail is affordable and probably the easiest way to send lightweight packages such as letters and envelopes
  • Second class mail is the best choice for sending magazines, newspapers, and periodicals
  • Easyship offers USPS First Class and Priority Mail at Commercial Plus Pricing (CPP), and you can easily compare the different services using our shipping rates calculator to determine which is best for you

The United States Postal Service (USPS) is one of the most popular courier solutions for eCommerce merchants. They offer a variety of options for both domestic and international shipping. The guide below outlines the difference between two common USPS shipping options, first-class vs. priority mail.

As an eCommerce business, you should consider several factors before settling for either of these shipping options. The cost and delivery timelines are probably crucial factors that determine your delivery option of choice. That said, read on for detailed priority vs. first class differences.

Table of Contents

What’s the Difference Between First Class vs. Priority Mail?

Differentiating between first-class mail vs. priority mail will ease your choice of shipping options. First-class mail is affordable and probably the easiest way to send lightweight packages such as letters and envelopes. It is considered a top-tier shipment option compared to second-class, third class, and fourth-class mail.

Second class mail is the best choice for sending magazines, newspapers, and periodicals. Third class suits flyers, mailers, and marketing mail while fourth–class mail is the best media mail, including vinyl records, books, DVDs, CDs, and other bound print media with more than eight pages.

On the other hand, priority mail is the USPS’s priority shipping option. The option is the best for eCommerce businesses looking to send their parcels faster. Besides being a quicker than first class mail option, it also allows sending heavier packages, up to 70lbs. Comparing the first-class package vs. priority mail, priority mail is a better alternative for sending international packages as it significantly reduces shipping time. However, due to the short delivery time, it is more expensive than first-class mail.

USPS priority mail vs. first class comparison aside, priority mail is comparably closer to FedEx and UPS shipping services. However, first-class mail is more economical than FedEx and UPS pricing models, especially for packages weighing less than 10lbs.

Comparing First Class vs. Priority Mail

Getting into the details of first-class vs. priority mail makes it easy to choose between these two options.

Which One is Faster?

Transit time is probably one of the crucial guiding factors when comparing first-class mail vs. priority mail. However, before making a decision, it is worth noting that both shipping options are great as they provide between two and three-day delivery timeframes. Since USPS uses shipping zones in classifying the delivery times, below is a comparison table of priority vs. first-class transit times for domestic and international shipments.

Domestic Zone 1 Zone 3 Zone 5 Zone 8
USPS First Class 2 days 3 days 2–3 days 3 days
USPS Priority Mail Express 1-2 days 1-2 days 1-2 days 1-2 days
USPS Priority Mail 1 day 2 days 2 days 3 days
International Estimated Transit Time
USPS First Class Mail International No exact time
USPS Priority Mail Express International 3-5 days
USPS Priority Mail International 6-10 days

Packaging Dimensions and Weight

Another crucial difference when looking at these services are the package dimensions and weight. Unlike priority mail, first-class mail has several weight and size specifications for sending packages. Postcards, envelopes, and letters, for instance, have weight and dimensions specifications; on the other hand, priority mail packages should not exceed 70lbs. Businesses with packages that exceed the size and weight limits are subjected to additional restrictions.

That said, the maximum dimensions for USPS first class mail and priority mail should not exceed 108”. Note that this is the combined girth and length of the parcel. On the other hand, the maximum mail weight for USPS first class mail is 15.99oz, while USPS priority mail can ship up to 70lbs.


The price details for USPS priority mail vs. first class vary depending on several factors. Unlike other couriers, USPS regularly change their postal rates according to inflation. However, customers often spend less by sending their shipments with first class mail compared to priority mail. This is because priority mail fees are based on the distance.

The cost of sending a package using first-class mail significantly depends on the shipment weight, size, and destination. Priority mail often has fixed rates for specified boxes and envelopes. Parcels shipped using priority mail and first-class mail to the same destination often have a $3 difference in most situations.

An example of a 9 by 12-inch measuring envelope that weighs 13 ounces sent from Pittsburgh to Pennsylvania would cost $3.52 if sent with first-class mail. The same package sent the same distance would take two days and cost $7.15 for those using their packaging and $6.70 for senders using the flat rate option of priority mail. Similarly, a 13-ounce shipment costs $5.50 for first-class, $7.50 for 2-day priority mail, and $7.20 for flat rate small box priority mail option.

Related: 2021 USPS Shipping Rate Changes
USPS Priority Mail

First Class vs. Priority Mail Shipping Features

Apart from the cost and delivery time frame, other factors bring out differences between USPS first class mail vs. priority mail. Some of the key features to note include:

Insurance: probably the advantage that priority mail has over first-class mail is the included insurance coverage that compensates for packages that get lost or incur damages during transit. Unlike priority mail, first class mail has no default insurance coverage. Priority mail offers up to $100 coverage for domestic shipments and $200 default insurance coverage for international coverage. Fortunately, you can purchase additional coverage through USPS or third-party service providers.

Tracking: unlike insurance, both first-class mail and priority mail offer tracking updates until the packages arrive at the intended destination. This includes the delivery date and time or attempted deliveries in case of missed deliveries. Tracking services are available for both shipping options at no cost.

Other additional shipping features to note when comparing USPS first class package vs. priority mail include the availability of money-back guarantee, weekend deliveries, signature services, certified mail, cost of return receipts, special handling, and mailing certificate.

When to Use First Class vs. Priority Mail

Making a choice between first class mail vs. priority mail comes down to a few factors. USPS first class mail is a cost-effective shipping option for sending packages under 1lb, specifically for typed or handwritten letters, postcards, thick/big envelopes, brochures, and ordinary bills.

Priority mail is going to be a better option if you are sending heavier or larger packages that you want delivered quicker. You’ll have the added benefit of free tracking and insurance with this option as well.

USPS Shipping with Easyship

Easyship offers USPS First Class and Priority Mail at Commercial Plus Pricing (CPP), and you can easily compare the different services using our shipping rates calculator to determine which is best for you. With Easyship, you can get the most out of your USPS shipping with seamless management: schedule pickups, generate shipping labels and scan forms in addition to tracking your shipments.

Sign up today for a free Easyship account and gain access to discounted USPS rates!

First Class vs. Priority Mail FAQ

Can I ship first class mail in a Priority Mail box or envelope?

Priority Mail boxes or envelopes are only for Priority Mail.

Does first-class mail really only take 1-3 days for delivery?

Yes, first-class mail takes 1-3 business days. However, there can always be an unexpected occurrence.

How accurate is the USPS Priority Mail Map?

The USPS Priority Mail is accurate for calculating delivery lead time.

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