Originally Posted by AskAndyAboutClothes
Belt sizes are two inches wider than your waist size in even numbers. So if your waist measurement is 34 you buy a 36 belt. Belts are sold only in even number sizes. If your waist is an odd number, 33 for example, it's better to go up one notch to a 36 belt and not the 34. The buckle tongue should fit into the center hole (usually #3 since most belts have five holes) so that the tail ends up just past the first loop on your pants. Andy
This is flat out untrue unless the pants are vanity sized.
Belt size and pant size should be the same. If they're not, something is wrong. When clueless salesmen tell you to buy the next size up, they are wrong.
Seriously, take out a tape measure. Buckle to center hole should measure out to the size of the belt. All of mine certainly do.