The IceCube Neutrino Observatory features a kilometer-cubed deep detector and a surface component, IceTop. IceTop consists of 162 ice-filled tanks equipped with optical sensors capable of detecting charged particles produced in air showers. While IceTop is well known for its cosmic-ray spectrum and mass composition measurements, it can also be used as a veto for IceCube. This role is becoming more important in the design of a larger surface array. High-energy neutrinos are absorbed by the Earth, therefore detecting neutrinos from the southern hemisphere is a priority. An efficient veto, however, requires suppressing the large background consisting of penetrating atmospheric muons and neutrinos. A surface array like IceTop can reduce the background by identifying particles which are generated in the same air shower as the muons in the deep detector. The capabilities and limitations of IceTop as a veto for cosmic rays will be presented.