How Long To Cook Porterhouse Steak Medium Rare

There is nothing quite as jaw-dropping as a massive, perfectly grilled porterhouse steak. Using simple techniques and great seasoning, you can grill a tender and delicious porterhouse steak at home.

Medium rare porterhouse steak, sliced and arranged in a cast iron skillet with garlic cloves and thyme sprigs.

What is a Porterhouse Steak?

A porterhouse steak is a massive cut of beef comprising two separate muscles divided by a thin bone. The larger side of the porterhouse steak is a New York strip steak and the smaller side is a tenderloin. Most porterhouse steaks are cut very thick (at least 1.5 inches), weigh in at about 24 oz total, and can easily feed multiple people.

Overhead view of a porterhouse steak on a wood cutting board.

Porterhouse Steak vs. T-Bone

Both porterhouse and T-bones are cut from the short loin, both contain the same two cuts of meat (the New York strip and the tenderloin), so it begs the question… What is the difference between a porterhouse and a T-bone?

The biggest difference in these two cuts boils down to the size of the filet. The United States Department of Agriculture has specific guidelines regarding the size of the filet that separates the T-bone from the porterhouse.

For a T-bone to qualify as a porterhouse, the USDA states that the filet is required to be at least 1.25 inches thick. This measurement is taken from the bone to the widest point on the filet. The T-bone comes from the front portion of the short loin where the tenderloin tapers off, so the filet portion on T-bones are often very small. The Porterhouse steak is cut from the rear of the short loin where the tenderloin is the thickest. On a Porterhouse, you'll see a sizeable portion of filet.

Porterhouse steak seasoned with salt and pepper based seasoning on a grill.

What is Reverse Searing?

With a thick cut of steak, like a porterhouse, my preferred method of grilling is using a technique called reverse searing. This process involves grilling the steak at a lower temperature over indirect heat and searing at the end over high heat. Reverse searing works exceptionally well with thick cuts because it allows the temperature of the steak to rise slowly. As a result, your steak will have the perfect doneness edge to edge instead of having steak that is charred on the outside and under-cooked in the middle.

How to Cook/Grill a Porterhouse Steak

The following is a guide to help you prepare for the grilling process. Full instructions will be in the recipe card below.

Here's how to do it:

Prepare your grill. You can use a gas grill, a charcoal grill, or a smoker. You'll want to preheat it to 225 degrees F and have a spot on your grill where your steak can slowly come up in temperature without being exposed to any direct heat.
Season your steak. Great steak doesn't need much. I recommend using my Signature Beef Seasoning (the 2020 NBBQA 1st place winner in the beef seasoning category). Equal parts salt and pepper work great also!
Cook your steak. Place your steak on the preheated, low temperature grill, over indirect heat. Close the lid and let your steak slowly rise in temperature. This step will likely take about an hour if you are hoping to end up with a medium rare steak. You want to take your steak off of the grill when it reaches 10 degrees under your desired finished temperature.
Sear your steak.For that coveted, crispy crust, you need a sear on your steak. I recommend searing in a hot cast iron skillet with avocado oil, butter, garlic, and fresh herbs (like thyme).
Rest your steak. Pull your steak out of the skillet and allow it to rest for at least 15 minutes before cutting the individual steaks off the bone and into slices.

Close up of thermometer inserted into a porterhouse steak reading 125 degrees F.

How Long to Grill Porterhouse Steak

Plan on the entire reverse searing process taking about an hour and a half for a medium rare steak. One hour over indirect heat, fifteen minutes for the searing process, and fifteen minutes of steak resting. These are large steaks and you definitely don't want to rush the cooking process and end up with over or under-cooked steaks.

Of course, the total cook time for your steaks will depend on your desired steak doneness. A rare steak will require less time on the grill and a well done steak will take quite a bit longer. I always recommend using a high quality meat thermometer when it comes to grilling steaks. With an instant read thermometer, you don't have to guess at the interior temperature of thick steaks.

Porterhouse Steak Temperature

For a simple guide on steak temperatures and doneness, check out my Steak Temperature Guide post. It will really help ensure you end up with the steak doneness that you prefer when cooking steaks. I also have a downloadable meat temperature guide that you can print out and have handy in your kitchen. Just enter your email in the box below and I'll email it to you.

How to Cook Porterhouse Steak in the Oven

The process for this recipe is simple to replicate in the oven with a few small modifications.

Preheat your oven to 225 degrees F, instead of your grill.
Place the steak onto a baking sheet and into the oven, instead of directly on the grill grates.
Follow the searing instructions in a skillet, as written.

Porterhouse steak sizzling in a cast iron skillet with butter, oil, garlic cloves, and thyme sprigs.

More Steak Recipes

If you're a steak lover, you won't want to miss out on some of these other steak recipes I've got on the site!

How to Grill Steak
Marinated and Grilled Flank Steak
Reverse Seared Tomahawk Steak

Porterhouse Steak Recipe

Sliced porterhouse steak in a cast iron skillet garnished with garlic cloves and thyme sprigs.

Porterhouse Steak on the Grill

There is nothing quite as jaw-dropping as a massive, perfectly grilled porterhouse steak. Using simple techniques and great seasoning, you can grill a tender and delicious porterhouse steak at home.

Prep Time : 15 mins

Cook Time : 1 hr 10 mins

Resting Time : 10 mins

Total Time : 1 hr 35 mins

Servings : 2 people

Calories : 637 kcal

▢ 1 porterhouse steak (24 oz, about 2 inches thick)
▢ 1 Tablespoon Signature Beef Seasoning

Searing Ingredients

▢ 4 Tablespoons avocado oil
▢ 4 Tablespoons butter
▢ 2 cloves garlic (smashed)
▢ 2 sprigs fresh thyme

Preheat the grill. Preheat your grill or smoker to 225 degrees F with indirect heat. If smoking, use your favorite hardwood like oak, hickory, or pecan.
Season. Remove your steaks from the refrigerator and season on all sides with the Beef Seasoning (or simply salt and pepper).
Cook the steaks. Place the steaks on the low temperature grill and close the lid. Slow cook the steaks for 30 minutes before flipping. Close the lid and cook again for approximately 30 more minutes.
Remove and rest. Use a meat thermometer to check the internal temperature of your steaks during the cooking process. You will want to pull the steak off of the grill and onto a plate about 10 degrees before your desired doneness. For example, if you want to end with a rare steak, pull your meat off of the grill at 115 degrees F. 125 for Medium Rare, 135 of Medium, 145 for Medium Well, 155 for Well Done. Bring the steaks inside to rest while you prepare for the next step.
Heat the oil. In a large cast iron skillet, preheat the 4 tablespoons of avocado oil over medium high heat until the oil starts to visibly ripple and shimmer in the pan.
Sear the porterhouse steaks. Place the steak in the pan gently and then add in the garlic cloves and thyme. Don't move the steak for at least 2 minutes while the crust develops. You should be able to hear it sizzle. Flip the steak in the pan to sear the other side. At this point, add the butter to the pan. Use a large spoon to baste the hot butter and garlic seasoned oil onto the top of the steak during the last 2 minutes of pan searing.
Remove and rest. Remove the steak from the pan when they near your desired finished temperature. 125 degrees F for Rare, 135 for Medium Rare, 145 for Medium, 155 for Medium Well, 165 for Well Done. Allow the steaks to rest for 10 minutes.
Slice and serve. When the steak is done resting, slice the tenderloin and the strip steak away from the bone and slice. Arrange on a serving platter with the bone and drizzle the top with the pan juices. Serve with the roasted garlic and, if desired, crumble the fried thyme leaves on top of the sliced steak. You can also finish with a sprinkle of flaky sea salt.

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