GO:0015127:   bilirubin transmembrane transporter activity
Enables the transfer of bilirubin from one side of a membrane to the other. Bilirubin is a linear tetrapyrrole produced in the reticuloendothelial system from biliverdin and transported to the liver as a complex with serum albumin. In the liver, bilirubin is converted to bilirubin bisglucuronide, which is excreted in the bile.