Smoke an 18 lb Brisket at 250°F for 12-16 Hours

An 18 lb brisket smoked at 250°F typically takes 12-16 hours, or 1-1.5 hours per pound, including rest time. Cook until the internal temp hits 195-203°F for tender results. Factors like fat content, stall duration, and smoker consistency affect timing.

Key Factors Affecting Cook Time

  • Fat cap thickness: More fat = longer render time.
  • The stall: Evaporation cools the meat at ~150-170°F, adding 2-4 hours.
  • Smoker stability: Fluctuating temps extend cook time.
  • Brisket grade: Higher marbling (e.g., Prime) cooks faster than Lean.

Step-by-Step Time Breakdown

  1. Prep (30-60 mins): Trim fat, apply rub, let sit at room temp.
  2. Smoke (8-12 hours): Maintain 250°F until internal temp reaches 165°F (stall begins).
  3. Stall (2-4 hours): Wrap in butcher paper/foil at 165-170°F to push through.
  4. Finish (1-2 hours): Cook to 195-203°F (probe-tender).
  5. Rest (1-2 hours): Hold in a cooler/towel to redistribute juices.

Cook Time Comparison by Weight & Temp

Brisket Weight Temp (°F) Estimated Time Time per Pound Fuel Use
12 lb 225 14-18 hours 1.2-1.5 hours High
18 lb 250 12-16 hours 1-1.2 hours Moderate
18 lb 275 10-12 hours 0.8-1 hour Low

Pro Tips to Speed Up or Slow Down

  • Speed up:
    • Increase temp to 275°F (sacrifices slight tenderness).
    • Trim excess fat to reduce render time.
    • Wrap early (at 150°F) to minimize stall.
  • Slow down:
    • Cook at 225°F for deeper smoke flavor.
    • Avoid wrapping to extend bark development.
    • Use a water pan to stabilize humidity.

Signs Your Brisket Is Done (Beyond Time)

  • Probe test: Slides into thickest part like butter (203°F max).
  • Bend test: Picks up easily when lifted; cracks slightly in the flat.
  • Visual cues: Bark is dark mahogany; fat renders but isn't crispy.
  • Juices: Run clear (not red) when pierced.