The t-bone steak comes from the front of the short loin.
This side is used because the tenderloin muscle is smaller.
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Depending on the size of the cow and how the Butcher decides to cut:
There are roughly 10-20 t-bone steaks per cow (assuming 0.75 – 1.25 inch thick steaks).
Why is it Called a “T-bone”?
The shape of the bone is a “T.”
The T itself:
- The center bone is a transverse process of the vertebra.
- The top of the T is half the vertebral foramen.
That may be hard to understand, so here are those parts visually:
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If we zoom back even more (assume you’re staring at the cow from the back):
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What Muscles Make Up the T-bone Steak?
There are 2 muscles:
- the strip loin
- the tenderloin
The strip loin is the larger muscle.
This is pictured in dotted yellow line below:

The tenderloin is the smaller muscle on the other side of the bone.
This is pictured in dotted yellow line below:

The above steak was sold to me as a T-bone steak BUT, since the tenderloin was wider than 1.25″, it’s technically a porterhouse.
Anything smaller than 1.25″ is a t-bone.
For example:
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Quite literally a single bite.
Often these steaks are de-boned and the muscles themselves are made into retail cuts like:
- NY strip steaks
- Tenderloin medallion steaks
- Whole tenderloin
- Whole strip loin