Roast (fat side up, in cooking bag with seasonings and 1 cup water) at 250F for…

  • 3-4 pounds, 2.5 hours
  • 5-6 pounds, 3 hours
  • 7-8 pounds, 3.5 hours
  • 9-11 pounds, 4 hours

Check temperature of meat 1 hour before suggested completion time. Target temperatures are as follows.

  • Rare, 120F
  • Medium Rare, 130F
  • Medium, 140F

Source

Greg’s Meats (Hampton, MN) provided these instructions with their prime rib, but the YouTube video of Greg’s Twin Cities Live appearance is also quite helpful.

Comments

2025-12-25 (Jack)

Mike got a 12.2-pound prime rib this year, and it only took 3 hours to get to 120F (where we pulled it). It was cooked perfectly to our liking, but it makes me believe that the suggested cooking times are targeting a much further doneness than we want.