The T-bone an Porterhouse are steak cuts of beef. They consist of a T-shaped bone with meat on each side. The larger side contains meat from the strip loin, whereas the smaller side contains the tenderloin. T-bone steaks from the rear end of the tenderloin contain a much larger section of the tenderloin, and are called porterhouse steaks. In British usage, followed in Commonwealth countries, only the strip loin side is called the porterhouse, and the tenderloin side is called the fillet.