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How long to smoke an 18 lb turkey at 275°F
Mike Ross · How we research · Updated 2026-08-30
At the grate
9h – 11h 42m
Rest
21m – 45m
Cook plus rest
9h 21m – 12h 27m
Plan for
12h 27m
The long end, always
When to light it
Work backwards from the long end. To serve an 18 lb turkey at 6pm on a Saturday, light the smoker around Saturday 5:33am — 12h 27m earlier.
That asymmetry is deliberate. Finished barbecue sits in a cooler for hours and arguably improves; an unfinished one at dinner time is not a problem you can solve. Being early is recoverable, being late is not.
The smoker calculator turns your own serve time into a clock time, and handles weights and temperatures between the ones charted here.
This is an overnight cook
At 12h 27m you are not staying awake for this. There are two workable plans and one bad one.
Start the evening before and sleep through the long middle stretch — a pellet grill holds its own temperature, which is what makes this the common choice. Or start at dawn and hold it: finish in the afternoon, wrap it, and rest it in a dry cooler until dinner. A well-packed cooler holds serving temperature for hours, and the rest does the meat good.
The bad plan is starting in the morning and hoping. That is the version where dinner is at 11pm.
Why this is a range and not a time
The same turkey can finish hours apart between cooks. Grade, fat, airflow, ambient temperature and how often the lid comes off all move the number, and a calculator can see none of them.
So the figures above are the published window, not a prediction. A page that told you “11h 42m exactly” would feel more precise and be less true.
What temperature to pull it at
Pull between 165–175°F internal. The USDA safe minimum for this cut is 165°F, which is a food-safety floor rather than a target.
Below 275°F the skin does not render properly. Breast to 165°F, thigh to 175°F.
Safe minimums from the USDA FSIS Safe Minimum Internal Temperature Chart.
How much fuel it takes
On a pellet grill at 275°F, this cook burns roughly 11.3–20.5 lb of pellets — so have two 20 lb bags on hand. Cold and windy days push that higher.
For an offset or a charcoal cooker there is no figure here, and that is on purpose. Consumption depends on firebox size, wood species, split moisture and how the pit is run, and a number would be a guess wearing an estimate’s clothes.
The same cut at other temperatures
Published figures for turkey run 275–325°F. Outside that range we have no chart to work from and will not extrapolate one.
Other weights at 275°F
What this cook actually needs
Every figure on this page is a range, and the only thing that closes it is measuring the internal temperature — more so on a cut this quick, where the window between done and dry is narrow.
Bear Mountain Hickory BBQ Pellets
Hardwood pellets with nothing else in them. The default fuel for any pellet grill.
- Wood
- 100% hardwood, hickory over an alder or oak base
- Bag sizes
- 20 lb and 40 lb
Hardwood pellets
Check current price on AmazonCommon questions
- How long to smoke an 18 lb turkey at 275°F?
- 9h – 11h 42m at the grate, plus 21m–45m of rest. Plan 12h 27m in total and hold it if it finishes early — finished barbecue keeps, unfinished barbecue cannot be hurried.
- What internal temperature should an 18 lb turkey be pulled at?
- 165–175°F. The USDA safe minimum for this cut is 165°F, which is a food-safety floor rather than a target. Below 275°F the skin does not render properly. Breast to 165°F, thigh to 175°F.
- Can you smoke an 18 lb turkey faster than 275°F?
- Yes, within limits. Published figures for this cut run 275–325°F, and the hottest of those brings the cook down to 9h at the long end. Past that range we have no published chart to work from and will not guess.