Asymmetrical breasts can make finding the right fit a troublesome task. To avoid problems of a too small cup, such as wires that pinch or breast tissue spilling over the top, always favour the bigger breast while selecting a bra. Overspill is more visible under your clothing than a bra cup that isn´t entirely full.
You can use padding on your smaller breast or bra styles that are suitable for uneven breasts. Consider a bra with a stretchy cup material. Stretchy cup fit well without wrinkling or bulging even though your breasts are not completely symmetrical. The most common alternative for different sized breasts is a half-padded bra with stretchy lace or mesh panel at the top part of the cup. Thick padding or moulded cups keep their shape and don´t adjust to the breast tissue, which may bring out even more the asymmetry and empty space in the cup of smaller sized breast.