Porterhouse
Porterhouse is a bone-in beef steak cut from the rear of the short loin primal. The T-shaped vertebral bone separates a strip steak section on one side from a tenderloin section on the other. To qualify as porterhouse under USDA standards the tenderloin section must be at least 1.25 inches (32 mm) wide at its widest point; below that threshold the same cut is sold as T-bone.
Porterhouse is a bone-in beef steak cut from the rear of the short loin primal. The T-shaped vertebral bone separates a strip steak section on one side from a tenderloin section on the other. To qualify as porterhouse under USDA standards the tenderloin section must be at least 1.25 inches (32 mm) wide at its widest point; below that threshold the same cut is sold as T-bone.
Porterhouse is taken from the rearmost portion of the short loin, where the tenderloin tapers to its largest diameter. That makes the tenderloin half of a porterhouse meaningfully bigger than the tenderloin half of a T-bone, the only real difference between the two cuts. Most porterhouses are 1.5 to 2 inches thick to balance the two muscles cooking at similar rates.
In Italy the same anatomical cut is called bistecca alla Fiorentina when grilled over hardwood; it is traditionally cut very thick (4 to 6 cm) and served rare, sliced. The two-muscle nature is the appeal: one bite of strip-loin chew and beef flavor, one bite of tenderloin softness, side by side.
Also known as: Porterhouse steak, King steak, Bistecca alla Fiorentina (Italy, large).
What good quality looks like
- A clearly visible tenderloin section at least 1.25 inches (32 mm) wide on the smaller side of the bone
- Even thickness across both muscles to avoid uneven cooking
- Good marbling on the strip side; the tenderloin side is naturally lean and shows little marbling
- Bright cherry-red lean on both muscles, no graying near the bone
- Clean cut bone with no shattering, indicating careful butchery
How to cook it
- High-heat grill or pan sear, target 52-54°C / 125-130°F for medium-rare on the strip; the tenderloin will run slightly more done
- Position the tenderloin side away from the hottest part of the grill so it does not overcook
- Rest at least 8 minutes before slicing the meat off the bone
- Slice the strip and tenderloin off the bone, then portion across the grain for serving
Frequently asked
What is the difference between porterhouse and T-bone?
They come from the same primal and have the same T-shaped bone. The difference is the size of the tenderloin section: porterhouse must be at least 1.25 inches wide on the tenderloin side; T-bone is anything smaller. Porterhouse comes from further back on the carcass where the tenderloin is bigger.
Why are porterhouses more expensive than T-bones?
You are paying for the larger portion of tenderloin, which is the most-prized muscle on the carcass. The strip portion is similar, the tenderloin portion is bigger, and only the rearmost section of the short loin yields true porterhouses, so they are scarcer.
How thick should a porterhouse be?
Most porterhouses are cut 1.5 to 2 inches (38 to 50 mm) thick. Thicker than that and the strip side overcooks before the tenderloin reaches temperature; thinner and you cannot get a sear without overcooking the tenderloin.
Is porterhouse the same as bistecca alla Fiorentina?
Anatomically yes, the same two-muscle T-bone steak. Bistecca alla Fiorentina is specifically the Tuscan preparation: very thick, traditionally from Chianina cattle, grilled over hardwood, served rare and sliced. Same cut, different presentation.