
I selected standard dimensions for boxes from 1 to 6 cubic feet. How I calculated shipping prices for UPS, USPS and FedExįor boxes, I started at "small big" and got bigger. Once you have a billable weight and a zone, you can simply match up your numbers on the pricing charts for FedEx, UPS and the US Postal Service to see how much your package will cost. For example, in our 24-inch x 24-inch x 18-inch example, the weight was 30 pounds, but the dimensional weight would be much higher - 63 pounds for UPS and USPS, or 78 pounds for FedEx. The billable weight of your package will be whichever number is higher - the weight in pounds or the dimensional weight. Just watch your weight on the lighter packages - bumping up our 12-inch x 12-inch x 12-inch box from 5 pounds to 10 pounds for its trip from California to Kansas increases its Priority Mail price by almost 50%, from $21.35 to $31.50.

Instead of cramming all your gifts into the 12.25-inch x 12.25-inch x 6-inch large Priority Mail flat-rate box from USPS, you can spend just a few dollars more to send a box that's significantly bigger. It's interesting to notice that Priority Mail prices for shipping larger than 5-pound packages are less than $2 more than the flat rate for a large Priority Mail box - usually $19.95 - even though our box has about twice the volume. The prices for three-day delivery increase significantly at UPS and FedEx, with the former listing prices three or four times higher for small boxes, about 50% to 125% more for medium boxes, and two to three times higher for the largest boxes. The takeaway on three-day shipping? If you have access to a US Post Office and you're willing to wait in line, you'll save quite a bit using Priority Mail to get your packages where they need to go in about half a week.
