Is USPS Ground Advantage the cheapest USPS service?
For almost every box on this page, yes. Priority Mail costs more and buys you a day or two, and both include tracking. Ground Advantage is the sensible default under about 10 lb.
USPS
How much does it cost to ship a package with USPS?
USPS Ground Advantage quoted $8.94 for a 12 × 9 × 6 in 5 lb box from New Jersey to Chicago, and USPS was cheapest on most of the light boxes we ran. Everything in the tables below was quoted through the SMKlog calculator on 2026-07-24. The prices are all-in — the carrier label plus what SMKlog charges — and nothing is added at checkout.
Live parcel ratesReal quotes, datedTracking included
Every number here is a real quote
Prices on this page came out of the SMKlog calculator on 2026-07-24 for the exact boxes and routes listed. Run yours for today's rate.
USPS prices on real boxes
| Box and weight | Cheapest USPS | Estimated transit | Other services quoted |
|---|---|---|---|
| 9 × 6 × 4 in, 1 lb | $11.05 Ground Advantage | 3-4 business days | Priority $14.49 |
| 12 × 9 × 6 in, 5 lb | $8.94 Ground Advantage | 3-4 business days | — |
| 16 × 12 × 10 in, 10 lb | $20.86 Ground Advantage | 3-4 business days | — |
| 18 × 14 × 12 in, 20 lb | $33.44 Ground Advantage | 3-4 business days | — |
| 24 × 18 × 18 in, 50 lb | no rate returned | — | — |
Coast to coast
| Box and weight | Cheapest USPS | Estimated transit | Other services quoted |
|---|---|---|---|
| 9 × 6 × 4 in, 1 lb | $13.00 Ground Advantage | 4-5 business days | Priority $16.47 |
| 12 × 9 × 6 in, 5 lb | $14.16 Ground Advantage | 4-5 business days | — |
| 16 × 12 × 10 in, 10 lb | $30.09 Ground Advantage | 4-5 business days | — |
| 18 × 14 × 12 in, 20 lb | $55.71 Ground Advantage | 4-5 business days | — |
| 24 × 18 × 18 in, 50 lb | no rate returned | — | — |
Small parcels
| Box and weight | Cheapest USPS | Estimated transit | Other services quoted |
|---|---|---|---|
| 6 × 4 × 2 in, 8 oz | $8.88 Ground Advantage | 3-4 business days | Priority $14.49 |
| 9 × 6 × 3 in, 1 lb | $10.89 Ground Advantage | 3-4 business days | Priority $14.49 |
| 10 × 8 × 4 in, 2 lb | $11.12 Ground Advantage | 3-4 business days | Priority $14.71 |
| 12 × 9 × 4 in, 3 lb | $8.88 Ground Advantage | 3-4 business days | Priority $17.66 |
Large parcels
| Box and weight | Cheapest USPS | Estimated transit | Other services quoted |
|---|---|---|---|
| 24 × 18 × 18 in, 30 lb | no rate returned | — | — |
| 30 × 20 × 20 in, 40 lb | no rate returned | — | — |
| 36 × 24 × 18 in, 50 lb | no rate returned | — | — |
| 48 × 24 × 12 in, 35 lb | no rate returned | — | — |
Where USPS returned nothing
Not every carton gets a rate from every carrier. On this run USPS returned no price for 24 × 18 × 18 in, 50 lb to Chicago, 24 × 18 × 18 in, 50 lb to Los Angeles, 24 × 18 × 18 in, 30 lb to Chicago, 30 × 20 × 20 in, 40 lb to Chicago. That is the carrier declining the box, not a gap in the data — the calculator simply shows you whoever did quote.
Common questions
When does USPS stop being the cheapest?
Around 20 lb and above in our run. At 20 lb USPS quoted $33.44 to Chicago while UPS Ground Saver quoted $23.00, and on the 24 × 18 × 18 in 50 lb carton USPS returned no rate at all.
Does USPS charge by size or by weight?
Both. Above a certain box size the dimensional weight — length × width × height ÷ 166 for USPS — takes over from the scale weight, and oversize surcharges start past 108 inches in length plus girth.
Are these USPS retail prices?
No. These are commercial rates bought online, which sit below the retail counter price. The number you see is the number you pay, label plus what SMKlog charges.
Can I drop a USPS label at any post office?
Yes, or hand it to your regular carrier, or schedule a free pickup on usps.com. Nothing about the label changes depending on how it enters the network.