What is Porterhouse Steak? Cut Explained - Barbecue FAQ (2024)

One of the most impressive cuts of steak on the entire cow is the Porterhouse; It’s a large cut of meat weighing around 2-3 lbs, cut to 2+ inches thick, featuring some of the most prized muscles on the animal.

To put it succinctly: The Porterhouse is a beef steak cut from the loin primal – specifically from the end of the short loin. It contains two muscles, the tenderloin and the strip loin. All Porterhouse steaks must have a tenderloin that is at least 1.25″ wide.

Where is the Porterhouse Steak on a Cow?

The Porterhouse steak is found in the loin primal of the cow; Specifically from the posterior end of the short loin primal (towards the sirloin), as pictured below:

The reason the porterhouse is taken from end of the short loin is because the tenderloin muscle becomes larger towards the posterior of the animal.

Conversely, it tapers – or becomes smaller – towards the front. The very tip of the tenderloin is removed to create the coveted “filet mignon” – the most tender steaks on the entire animal.

What Muscles Comprise the Porterhouse Steak?

The Porterhouse steak is primarily comprised of two muscles:

• Longissimus dorsi – strip loin side (the same as a NY Strip)
• Psoas muscles – tenderloin

These are pictured below.

The “strip loin” side is to the bottom in dotted yellow:

The “tenderloin” side is to the top, in dotted yellow:

The porterhouse does contain part of the gluteus medius muscle (which is the main muscle of the top sirloin).

Why the Distinction with Regards to the Tenderloin?

As we learned above, a Porterhouse must have a tenderloin that is at least 1.25″ in width.

This isn’t just a made up number either, it’s a requirement by the USDA:

“Item No. 1173 – Beef Loin, Porterhouse Steak– The steaks must be prepared from any IMPS short loin item. The maximum width of the tenderloin must be at least 1.25 inches (3.2 cm) when measured parallel to the length of the back bone.”

Pg 75. IMPS. 9.30.2020

To understand what that “measurement” means, here’s a picture:

See Also

Understanding the Porterhouse Steak — What it is, and How to Cook it

So we’re essentially measuring from the transverse process, across the tenderloin muscle.

In the photo above, the tenderloin muscle is 2.5″ wide, meaning, it’s a Porterhouse steak. If the tenderloin muscle is less than 1.25″, it would be sold as a t-bone steak.

Here’s an example of a t-bone steak with a small tenderloin muscle:

Meaning, all Porterhouse steaks are t-bones, but not all t-bones are Porterhouse steaks.

Why Does the Width of the Tenderloin Muscle Matter?

The distinction with regards to the width of the tenderloin muscle has to do with the sale of t-bone and porterhouse steaks.

The t-bone steak and the porterhouse steak contain much the same musculature and bone – ie. the strip loin, tenderloin, and “t-bone.”

Since the tenderloin muscle is one of the most prized on the entire animal, a Butcher wants to maximize their profits by doing one of three things:

1. Isolating this musculature – ie. deboning the t-bone and selling strip cuts (whole strip loins or NY strip steaks) and tenderloin cuts (whole or filets/steaks).
2. Cut the steaks into both t-bone and porterhouse steaks.
3. Sell them all as t-bone steaks but cut thin for grilling/pan searing as apposed to 2+ inches thick.

To sort of prove this with regards to price-per-pound of all these steaks/roasts/sub-primals, we can use the pricing on Wild Fork Foods (as of 9/5/2023):

As we can see – the strip loin is the cheapest section and it’s essentially the cheapest cut of steak.

The tenderloin is more desirable and has a higher price per pound.

Due to this, the porterhouse is $1/lb more than the t-bone steak – it also weighs 1+ lb more and costs 1.8x more upfront.

Where Does the Name “Porterhouse” Come From?

While there isn’t really a definitive answer to this question, people suspect that the name stems from the word “Porter-house” used to describe a restaurant or Tavern in the 1800s.

Porter houses were so-called because they served a style of beer called a “Porter” – a dark-brown malty beer.

Aside from selling beer and liquor, these taverns also offered a few different hot meals, one being a large steak – hence a porterhouse steak.

Here’s a source that refers to a Proprietor of a Tavern having steaks cut for the “porter-house”:

“The origin of the name of “porter-house steaks” took place about the year 1814, in the following manner:

Martin Morrison was the proprietor of a long-established and well kept “porter-house,” located and known at that period at No. 327 Pearl-street (New York), near the “old Walton House.” We introduce him in 1803, where we find he opens a “porter-house” at No. 43 Cherry-street, which became a popular resort with many of the Kew York pilots for his prepared hot meals, at any hour, at their call, they being occasionally detained on shipboard until their vessels were safely moored….”

“…Morrison’s butcher – Thomas Gibbons – in the Fly Market, one morning put the question, after he (Morrison) had selected several sirloin pieces, “Why he had ceased purchasing the usual quantity of sirloin steaks?” Says Morrison, “I will tell you the reason: I cut off from the sirloin roasting-pieces a small steak which serves my pilots and single patrons best; but as it is now cold weather, I wish to have these roasting-pieces cut up as I shall direct every morning.” After this, Morrison’s sirloins were daily cut up by Mr. Gibbons, with his order to “cut steaks for the porter-house,” hence the sirloin was changed into “cut the porter-house steaks.” Their appearance attracted the attention of other butchers and keepers of porter-houses, who admired their appearance and convenient size; in a few years their name and character became quite common to the butchers of the Fly Market, from which the name has spread to the several principal cities of the United States, and I doubt not that the name,porter-house steakhas reached across the Atlantic.”

The Market Assistant, pg 45, 46, 47, 48. – Thomas Farrington De Voe, 1867

Another source that sort of alludes to the fact that a “porterhouse” may have referred to any sort of beef steak cut from the short loin (ie. a strip loin without the t-bone):

• The Career of Puffer Hopkins by Cornelius Mathews, 1842

“But I guess I’ll take a small porter-house steak, without the bone, for this time only!”

The Career of Puffer Hopkins, pg 17 – Cornelius Mathews, 1842

How are Porterhouse Steaks Typically Cooked?

Often, porterhouse steaks are cut to the following parameters:

• 2-3 inches thick
• Weighing 2-3 lbs

Meaning, these “steaks” would more appropriately be called roasts.

Often, the goal with a roast is to achieve “wall-to-wall” finishing temperatures – typically medium-rare or medium – across the entire finished slice.

To illustrate, here’s a porterhouse steak I smoked/reverse seared:

The above is what I’d deem wall-to-wall doneness.

Here’s the crust after searing/butter basting:

In order to achieve these qualities, you have two options:

1. Sear first with the goal to achieve a crust from the start. Then after searing, you slow roast via convective heat (like in your oven) so-as to reach your desired internal temperature.
2. Slow roast first with the goal to get near your finishing temperature. Once near your finishing temperature you sear the steak to achieve an exterior crust.

Both methods work well and will accomplish the goals for Porterhouse steak: wall-to-wall doneness, and a crust.