USPS Ground Advantage is not First-Class Mail, but it replaced what used to be called First-Class Package Service. If you previously shipped small packages using First-Class Package Service, Ground Advantage is the direct successor to that service. First-Class Mail for letters and flat envelopes still exists as a completely separate product.
What Ground Advantage Replaced
On July 9, 2023, USPS discontinued First-Class Package Service and rolled it into a new offering called Ground Advantage. The new service combined three older products into one: First-Class Package Service (which handled packages under 16 ounces), Retail Ground (ground-only parcels), and Parcel Select Ground (high-volume ground shipping). Instead of choosing between those three options, shippers now use a single service for all ground-level package shipments.
This is where much of the confusion comes from. If you shipped lightweight packages through USPS before mid-2023, your label probably said “First-Class Package Service.” That exact service no longer exists. The replacement is Ground Advantage, and it covers the same types of shipments plus heavier ones that previously went through Retail Ground.
First-Class Mail Still Exists
USPS continues to offer First-Class Mail as a separate service for letters, postcards, and large envelopes (called “flats”). When you buy a stamp and drop a letter in a mailbox, that’s First-Class Mail, and nothing about it has changed. The 2026 USPS price schedule lists First-Class Mail and Ground Advantage as distinct services side by side.
The key distinction is simple: First-Class Mail is for paper correspondence and thin envelopes. Ground Advantage is for packages. If you’re mailing a birthday card, you use First-Class Mail. If you’re shipping a product in a box or padded mailer, you use Ground Advantage (or Priority Mail if you need faster delivery).
How Ground Advantage Works
Ground Advantage accepts packages weighing anywhere from 1 ounce up to 70 pounds, which is a much wider range than the old First-Class Package Service allowed. Delivery takes 2 to 5 business days for most domestic shipments, though packages headed to Alaska, Hawaii, or other offshore destinations may take longer. Actual transit time depends on where the package originates and where it’s going.
The service includes tracking on all shipments. Pricing is based on package weight and distance, similar to how the old services worked but consolidated under one rate structure. For lightweight items under a pound, Ground Advantage pricing is comparable to what First-Class Package Service used to cost. For heavier items, it competes with what Retail Ground previously charged.
When Ground Advantage Makes Sense
Ground Advantage is the go-to choice when you’re shipping a package and don’t need overnight or two-day guaranteed delivery. It sits below Priority Mail in both price and speed. Priority Mail offers 1 to 3 business day delivery and includes additional features, but costs more. If your shipment isn’t time-sensitive, Ground Advantage will usually be the cheaper option.
Small online sellers who previously relied on First-Class Package Service for lightweight items can use Ground Advantage the same way. The experience is essentially identical: you create a label, drop off the package, and it arrives within a few business days. The branding changed, but the basic service for small, lightweight packages works the same as before.
For packages that exceed 70 pounds or need guaranteed delivery by a specific date, you’ll need to look at Priority Mail Express or other USPS options instead. Ground Advantage does not come with a delivery guarantee.