Whole turkey cooking on a BBQ with indirect heat
    3 min read Planning Guide

    How Long to Cook an 18 lb Turkey on the BBQ?

    Short answer

    Spatchcocked: about 2.5–3 h. Whole: about 4–5 h. Both at 325–350°F (165–175°C) with indirect heat, plus 30 minutes of resting. Done when the breast reads 160°F (71°C) and the thighs 175°F (79°C).

    Quick guide

    BBQ turkey

    3 h 30 min Medium Serves about 14 people
    Turkey size
    Style
    Pull when the breast reads71°C / 160°F

    You need

    • 1 turkey, 18 lb (8.2 kg), fully thawed
    • Kosher salt (about 1 tsp per lb / 450 g)
    • Softened butter with herbs (optional)
    • 2–3 wood chunks: apple, cherry or hickory

    1. Spatchcock and dry-brine

      Cut out the backbone with poultry shears and press the bird flat. 24–48 hours ahead, rub all over with kosher salt (about 1 tsp per lb) and refrigerate uncovered. Pat dry before cooking.

    2. Set up indirect heat

      Fire on one side, drip pan on the other, 165–175°C / 330–345°F. Add 2–3 wood chunks.

    3. Cook

      Turkey on the cool side, skin up, lid closed — about 2.5–3 h. Start checking temperatures halfway.

    4. Check two spots

      Done when the breast reads 71°C / 160°F and the thigh 79–82°C / 175–180°F. If the breast gets there first, shield it with foil.

    5. Rest and carve

      Rest 30 minutes loosely tented with foil. The breast climbs to the safe 74°C / 165°F while it rests.

    Plan it around your serving time →
    Spatchcockedabout 2.5–3 h
    Wholeabout 4–5 h
    Grill temperature325–350°F / 165–175°C
    Servesabout 14 people

    Numbers for a 18 lb (8.2 kg) turkey on the BBQ: cooking times spatchcocked and whole, when to start for a 6 pm dinner, and how many it serves.

    Cook Time for an 18 lb Turkey

    With indirect heat at 325–350°F (165–175°C):

    StylePer pound18 lb turkey
    Spatchcocked8–10 minabout 2.5–3 h
    Whole13–16 minabout 4–5 h

    Wind, cold weather and lifting the lid all add time. Start checking temperatures halfway through.

    Schedule for Dinner at 6 pm (Spatchcocked)

    StepStart at
    Dry-brine1–2 days before
    Light the grill2:30 pm
    Turkey on2:45 pm
    Off to rest5:30 pm
    Carve and serve6:00 pm

    For a whole bird, put it on around 1:00 pm instead.

    Want to skip the guesswork?

    How Many People It Serves

    At 1¼ lb of raw turkey per person, an 18 lb bird serves about 14 people. That's 12 if you want leftovers, or 18 with lots of sides.

    Plan Your Turkey Cook

    Answer a few quick questions and get a full step-by-step plan.

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    Frequently Asked Questions

    How long does an 18 lb turkey take on the grill?

    About about 2.5–3 h spatchcocked, or about 4–5 h whole, at 325–350°F with indirect heat.

    How many people does an 18 lb turkey feed?

    About 14 people at 1¼ lb per person, or 12 if you want leftovers.

    What temperature is turkey done?

    Pull it when the breast reads 160°F (71°C) and the thighs 175–180°F (79–82°C). The breast reaches the safe 165°F while it rests.

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    How Much Turkey Per Person (and Exactly How Long to Cook It)

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