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Here’s How long It Takes To Smoke An 18 Pound Brisket

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How long to smoke an 18 lb brisket

If you’re wondering how long to smoke an 18 pound brisket for, then you have come to the right place.

Depending on how hot and fast or low and slow you are happening to be cooking your brisket at, you can expect anywhere from 9 to 18 hours of total cook time.

For hot and fast styles of brisket barbecuing, then you should lean more towards the lower end of that timeframe, for about nine hours long. 

If you happen to be smoking low and slow, then you should budget enough time to be sitting around the fire and feeding it wood for over 18 hours.

How long to cook an 18 lb brisket in oven

If you happen to be cooking an 18 pound brisket inside of your oven, then keep reading.

You will want to measure the temperature that you will be cooking it at. 

That is one of the most important things in determining the length of cook for any size of brisket.

For an 18 pound brisket cooked at around 225°F, you can certainly expect roughly 18 to 19 hours of total cook time. 

As you start to increase the ambient temperature to around 275°F or perhaps even 300°F, then you can certainly expect an average cook time of around 8 to 9 hours. 

As you can see, hotter temperatures have the propensity to significantly decrease your overall cook time. 

This is something that you should absolutely consider, and also know that if you smoke it or cook any type of brisket at these hotter temperatures, the results are just as good, if not better.

How do you smoke an 18 pound brisket?

If you want to know how to specifically smoke in 18 pound brisket, keep reading as well.

To smoke an 18 pound brisket you will need to firstly season it properly with kosher salt and black pepper. 

Make sure there is no openings within the seasoning, and also make sure to prep the smoker simultaneously.

This basically just helps you get a little bit more extra time on your hands since you are now being efficient and multitasking.

Once the smoker is fully up to your preferred temperature, and the brisket is seasoned, go ahead and throw it onto the smoker itself. 

All you have to do from this point on, is maintain relatively consistent temperatures, and pull the brisket off the smoker only when the internal temperature is at around 200°F.

How long to smoke a 18 lb brisket at 250

Smoking a brisket at 250°F is rather low and slow.

That means you can expect about a 1 pound per hour cook time for any weight of brisket. 

For an 18 pound packer brisket smoked at 250°F, you can expect a roughly 18 total hours of cook time.

If that is still way too long, but you don’t want to increase the ambient temperature, then you should certainly consider wrapping it once it reaches an internal temperature of a round 160°F.

Final Thoughts 

To smoke an 18 pound packer, it can take anywhere from 9 to over 18 hours to fully cook through and ensure the rendered collagen is probe tender.

This should be at around 200° an internal Fahrenheit temperature. 

As you start to cook your brisket at hotter temperatures around 300°F, you can certainly then lean more towards the 9 hour mark for the total cook time. 

Likewise, for the lower cook temps, you want to budget ahead in advance because it’s going to more than likely take you over 18 hours to cook it through.