UPS does not sell flat rate boxes, but UPS Simple Rate gives you the same idea: a fixed price set by the size of your package, not its weight or destination. Prices start at $12.20 for an Extra Small box and $30.95 for an Extra Large one, and the package can weigh up to 50 lb.
The difference from USPS is that you pick the size by volume and can use your own box. That makes the answer to “does UPS have flat rate boxes” a qualified yes. UPS has flat rate pricing, not a special box you must buy.
Holiday prices through January 17, 2027: USPS added a temporary price increase from October 4, 2026 to January 17, 2027 for Priority Mail Express, Priority Mail, USPS Ground Advantage and Parcel Select. During that window, retail Ground Advantage starts at $8.40, Priority Mail at $11.50 and Priority Mail Express at $37.05.
Priority Mail Flat Rate costs $13.90 for the envelope, $14.25 legal, $15.00 padded, $14.65 for the small box, $25.80 medium and $36.10 large ($34.65 APO/FPO/DPO). Priority Mail Express flat rate envelopes are $38.25, $38.55 legal and $39.25 padded. Prices in the rest of this article are the regular July 12, 2026 prices, which return January 18, 2027, and stamps, letters and Media Mail are not affected.
How UPS Simple Rate works
UPS Simple Rate charges one price for each of five size bands. You measure your packed box and find the band it fits.
You then pay that price for any U.S. destination. Weight and zone do not change the price as long as you stay inside the limits.
No UPS account or contract is needed. The program covers shipments within the 50 states only, and it does not cover international shipping.
UPS Simple Rate sizes and prices
The five bands are based on total volume in cubic inches. Multiply length by width by height of your packed box to find yours. The prices below are the starting prices UPS lists, so confirm the final price on the UPS Simple Rate page before you ship.
| Box size | Volume | Starting price |
|---|---|---|
| Extra Small | 1 to 100 cu in | $12.20 |
| Small | 101 to 250 cu in | $15.80 |
| Medium | 251 to 650 cu in | $18.95 |
| Large | 651 to 1,050 cu in | $24.85 |
| Extra Large | 1,051 to 1,728 cu in | $30.95 |
The top of the range is 1,728 cubic inches, which equals one cubic foot. A box that measures 12 by 12 by 12 inches sits right at that limit.
Which delivery speeds are covered
UPS lists four speeds for Simple Rate: next day, second day, three business days and five day delivery. The page does not say which UPS service name matches each speed, and the prices are shown as “starting at”. Check the price for the speed you want when you create the label.
If you need to understand the faster services first, see what UPS Next Day Air is.
The slower end of the range is covered in what UPS 2nd Day Air is.
Do you have to use a UPS box?
No. UPS says you can use your own packaging, as long as it stays within 1,728 cubic inches and 50 lb. A sturdy box you already have works fine.
The price depends on the volume of the box, not on whose logo is on it. UPS also sells branded boxes, and qualifying UPS Digital Connections customers can get box subsidies.
For a look at what UPS hands out for free and what it charges for, read UPS shipping boxes explained.
How to find your size band
Multiply the length, width and height of the packed box, all in inches. The result is the volume in cubic inches. Match it to the table above.
| Packed box (inches) | Volume | Band |
|---|---|---|
| 4 x 4 x 4 | 64 cu in | Extra Small |
| 6 x 6 x 6 | 216 cu in | Small |
| 10 x 8 x 4 | 320 cu in | Medium |
| 14 x 10 x 6 | 840 cu in | Large |
| 12 x 12 x 12 | 1,728 cu in | Extra Large |
These are worked examples of the math, not UPS quotes. A box that lands just over a band edge costs the next price up. Trimming a half inch of empty space can move you down a band.
How to buy a Simple Rate label
- Pack the item in your own box or a UPS branded box.
- Measure length, width and height, then work out the volume in cubic inches.
- Create the label online at ups.com/ship and choose Simple Rate.
- Attach the label, or take the mobile barcode or printed label to a UPS Store.
Return labels are also supported, so you can send a Simple Rate return to a customer or to yourself. Because no account is needed, a one time sender can use the service as easily as a seller.
If you would rather not print anything, UPS says you can bring a prepaid mobile barcode to any The UPS Store location instead of a printed label. Store staff scan the code from your phone and print the label there.
When UPS Simple Rate saves money
A flat price pays off when your package is heavy for its size or going far. Regular UPS rates depend on dimensional weight and zone, so a cross country trip costs more than a nearby one. Simple Rate removes that swing.
It pays off less for a light box going a short way, where a zone based rate can be lower. The fastest way to check is to run both prices side by side in the shipping cost comparison tool.
Simple Rate vs USPS Priority Mail Flat Rate
USPS Priority Mail Flat Rate works differently. USPS gives you set boxes and envelopes, and the price is fixed by the box you pick. Since July 12, 2026, the retail prices on Notice 123 are $13.65 for a Small box, $24.80 for a Medium box and $34.00 for a Large box.
| Feature | UPS Simple Rate | USPS Priority Mail Flat Rate |
|---|---|---|
| What sets the price | Volume of your box | The USPS box you choose |
| Your own box | Allowed | No, USPS packaging only |
| Envelope size item | From $12.20 (Extra Small) | $12.90 (Flat Rate Envelope), $14.00 (Padded) |
| Starting price, small size | $12.20 (Extra Small), $15.80 (Small) | $13.65 (Small box) |
| Price, mid size | From $18.95 (Medium) | $24.80 (Medium box) |
| Price, large size | From $24.85 (Large) | $34.00 (Large box) |
USPS also sells Priority Mail Express flat rate envelopes from $35.90, which is a different speed tier and not a fair match for Simple Rate ground pricing.
The two programs do not line up size for size, and the UPS figures are starting prices. Compare prices for your actual box, and do not assume one carrier is always lower.
For the USPS side, see Priority Mail Flat Rate.
The flat rate box selector helps you pick the right USPS box.
Who UPS Simple Rate fits best
Small sellers and one time senders are the natural users. There is no account to open and no contract to sign. You can price a box, pay and drop it off in one trip.
It also suits anyone who ships awkward boxes that cost a lot under dimensional weight rules. The flat band price is easier to predict than a zone chart. A seller can quote a customer a shipping fee before the box is even packed.
Common mistakes to avoid
- Guessing the volume instead of measuring the packed box. Padding adds inches, and inches move you into a bigger band.
- Assuming the starting price is the final price. UPS lists “starting at” figures, so check the label screen.
- Sending an item worth more than $100 without extra coverage.
- Trying to use Simple Rate for a package going outside the 50 states.
What happens if your box is too big or too heavy
Think of the limits as a hard edge. A package over 1,728 cubic inches or 50 lb does not qualify. UPS then charges its standard rates, which use dimensional weight and zone.
Declared value coverage with Simple Rate is $100 per package. Arrange coverage separately for anything worth more.
Timing questions are separate from price. The delivery time estimator helps you see how long a route should take.
The bottom line on UPS flat rate shipping
UPS has no flat rate box, but Simple Rate delivers flat pricing in five volume bands up to 50 lb. Bring your own box, measure it, and compare the price with USPS before you pay.
