As of 2014, the largest natural breast bra size on record is 102ZZZ, according to MadameNoire.com. The largest breast implant bra size on record is 164XXX.
The intimate apparel retailer Bare Necessities offers a bra cup size of N. As of 2014, this is the largest commercially available bra cup size from retailers in the United States. As extended cup sizes become more readily available, women are finally able to shop for undergarments that fit properly. In the past, women were limited to cup sizes between A and DD, which resulted in a lot of ill-fitting undergarments. In order to purchase a bra that fits properly, women are urged to get a professional measurement.