Now, you might be thinking, "what about oversized packages?" Like, what if you're shipping a refrigerator or a grand piano? Well, UPS has special rules for those kinds of packages, because, let's face it, they're just too big for their britches. They have something called "oversized package" rates, which are higher than regular rates, because, you know, it's just harder to ship something that's ginormous.
But here's the thing: UPS also has something called "package consolidation" which means they can combine multiple packages into one shipment, and charge you less - it's like they're trying to save you money or something! So, if you're shipping multiple packages to the same place, it might be cheaper to consolidate them, rather than shipping them separately.
Large Package Dimensions Ups at Thomas Lintz blog