Stacey,

Most kilt belts are either 2.25" or 2.5" wide, and the rectangular buckles you see worn with them are designed to fit on that width belt. (Note: I have seen kilt belts of 1.75" and 2" widths, as well, but generally not worn with this style buckle).

So I am afraid that you'll find these too wide to wear with jeans.