How Long to Smoke an 18 lb Brisket
An 18 lb brisket takes 13 h 30 m to 22 h 30 m at 250°F. Plan for 18 h 55 m; to serve at 6 pm, light the smoker by 8:15 pm the day before.
18 lb brisket at 250°F
13 h 30 m – 22 h 30 m
plan for 18 h 55 m · rest 60+ min · 8.3–12.4 lb cooked
18 lb brisket at every pit temperature
| Pit | Range | Plan | vs 250°F |
|---|---|---|---|
| 225°F | 22 h 30 m – 31 h 30 m | 27 h 55 m | 9 h slower |
| 250°F | 13 h 30 m – 22 h 30 m | 18 h 55 m | — |
| 275°F | 10 h 50 m – 18 h | 15 h 05 m | 3 h 50 m faster |
| 300°F | 9 h – 15 h 20 m | 12 h 50 m | 6 h 05 m faster |
Timeline to serve at 6 pm
| Step | Time |
|---|---|
| Light the smoker | 8:15 pm the day before |
| Meat on (after about 45 min of preheat) | about 45 min later |
| Stall near 155°F: wrap if you want to speed up | about halfway through |
| Pull at about 203°F, probe-tender | about 2 h before serving (rest plus a 1-hour buffer) |
| Rest, wrapped, in a dry cooler | 60–180 min, up to 4 h above 140°F |
| Serve | 6:00 pm |
Charcoal: about 33.5 lb for the cook. Feeds: about 26–39 people at 5 oz cooked each.
Nearby weights
| Weight | Range at 250°F | Plan |
|---|---|---|
| 16 lb | 12 h – 20 h | 16 h 50 m |
13 h 30 m – 22 h 30 m
Plan for 18 h 55 m at 250°F · 18 lb brisket (whole packer)
| Light the cooker | 21 h 45 m before serving |
| Stall | starts near 155°F |
| Pull at | about 203°F and probe-tender |
| Rest | 60–180 min |
| Cooked meat you get | 8.3 – 12.4 lb |
How we calculate
- Time range = weight × hours per pound from the sources below (ribs, chicken, tri-tip and belly are timed per piece).
- The plan sits 60% of the way from the short end to the long end. Finishing early is easy to fix with a longer rest; finishing late is not.
- Several pieces: time follows the biggest one, plus 10% when the smoker holds 3 or more.
- Wrapping: where a source gives wrapped times we use them; otherwise we take about 10% off for butcher paper and 20% for foil (our estimate).
- Light the smoker at: plan + rest + a 1-hour buffer + 45 minutes to light and settle it. Cooked yield is from the USDA Food Buying Guide.
- Spare ribs: our source gives one 5–6 hour estimate for pork ribs; we use it at both 225 and 250°F.
Sources disagree by an hour or more on big cuts; that spread is why we show a range. Always finish by internal temperature. Data as of Oct 2026. Full list of sources: How we calculate.
Related
FAQ
How long to smoke an 18 lb brisket?
An 18 lb brisket takes 13 h 30 m to 22 h 30 m at 250°F. Plan for 18 h 55 m; to serve at 6 pm, light the smoker by 8:15 pm the day before.
How long to smoke an 18 lb brisket at 225?
22 h 30 m to 31 h 30 m, plan for 27 h 55 m.
How long to smoke an 18 lb brisket at 275?
10 h 50 m to 18 h, plan for 15 h 05 m.
How many people does an 18 lb brisket feed?
About 26–39 people at 5 oz of cooked meat each; it yields 8.3–12.4 lb.