I had originally ordered a 38F and decided I needed to go up to 38G. There is no difference in the two sizes. I feel like a bra that was truly a cup bigger in the band size I bought would have made all the difference. It's comfortable enough, but I can tell it doesn't fit right. Disappointed because the bra is sturdy. The straps aren't made with a stretchy material that give out and are truly comfortable. The only thing wrong with this bra is that I can't try another size up without messing with band sizes.