Abstract: Methods and apparatus are provided for filtering electromagnetic interference (EMI) in an input/output port such as a uniform serial bus (USB) port. An electromagnetic interference filter for an input/output port transmitting both differential signals and single-ended signals between first and second input terminals and first and second output terminals suitably includes a differential mode filter electrically that is operable to reduce electromagnetic interference while passing the differential signals and a single-ended filter that is operable to reduce electromagnetic interference while passing single-ended signals of a different bandwidth from the differential signals.