An 18 lb turkey takes 4¼ to 4½ hours at 325°F unstuffed, or 4¼ to 4¾ hours stuffed (USDA). Thaw it in the fridge for 4–5 days first.
| 18 lb turkey | |
|---|---|
| Roasting time, unstuffed | 4¼ to 4½ hours at 325°F |
| Roasting time, stuffed | 4¼ to 4¾ hours at 325°F |
| Resting time | 20–30 minutes before carving |
| Thaw in the fridge | 4–5 days (24 hours per 4–5 lb) |
| Thaw in cold water | about 9 hours (30 minutes per lb) |
| For Thanksgiving (Nov 26), move it to the fridge by | Saturday, November 21 |
| For Christmas, move it to the fridge by | Sunday, December 20 |
| Feeds | about 18 people, or 12 with leftovers |
| Done when | 165°F in the thickest part of the thigh, the wing and the thickest part of the breast |
USDA roasting time for an 18 lb turkey
The USDA timetable for a whole turkey at 325°F gives 4¼ to 4½ hours unstuffed and 4¼ to 4¾ hours stuffed for an 18 lb bird (about 8.2 kg). Start checking at the low end and plan your day around the high end.
18 lb sits on the line between two rows of the USDA chart. We use the longer row, so you start checking early and never plan too short.
The USDA recommends cooking stuffing in a separate dish. If you do stuff the bird, the center of the stuffing must also reach 165°F.
What time should an 18 lb turkey go in the oven?
Subtract the roasting time and a 30-minute rest from when you want to eat:
| Dinner at | Turkey in the oven | Start checking the temperature | Out to rest by |
|---|---|---|---|
| 1:00 PM | 8:00 AM | 12:15 PM | 12:30 PM |
| 2:00 PM | 9:00 AM | 1:15 PM | 1:30 PM |
| 3:00 PM | 10:00 AM | 2:15 PM | 2:30 PM |
| 4:00 PM | 11:00 AM | 3:15 PM | 3:30 PM |
| 5:00 PM | 12:00 PM | 4:15 PM | 4:30 PM |
How long to thaw an 18 lb turkey
In the fridge: about 24 hours for every 4–5 lb, so 4–5 days. For Thanksgiving on Thursday, November 26, 2026, move it to the fridge by Saturday, November 21. For Christmas, by Sunday, December 20.
Ran out of time? Thaw it in its wrapping in cold water, allowing 30 minutes per pound (about 9 hours) and changing the water every 30 minutes. Cook it straight away. See how to thaw a turkey fast.
Nearby sizes
| Weight | Unstuffed at 325°F | Stuffed at 325°F |
|---|---|---|
| 16 lb | 3¾ to 4¼ hours | 4 to 4¼ hours |
| 18 lb | 4¼ to 4½ hours | 4¼ to 4¾ hours |
| 20 lb | 4½ to 5 hours | 4¾ to 5¼ hours |
How many people does an 18 lb turkey feed?
Allow about 1 lb of whole turkey per person, or 1½ lb for leftovers. An 18 lb turkey feeds about 18 people, or 12 with plenty of leftovers. More in how much turkey per person.
How to tell it's done
Use a food thermometer. The USDA says the turkey is safe at 165°F, checked in the thickest part of the thigh, the wing and the thickest part of the breast. Pop-up timers aren't reliable on their own.
In Canada?
Health Canada advises cooking a whole bird to 82°C (180°F), and thawing in the fridge allows about 24 hours per 2.5 kg (5 lb). See turkey thawing and temperatures in Canada.
Other sizes: 12 lb · 14 lb · 16 lb · 18 lb · 20 lb · full thawing chart
FAQs
How long does an 18 lb turkey take to cook?
4¼ to 4½ hours unstuffed at 325°F, or 4¼ to 4¾ hours stuffed (USDA). Then rest it for 20–30 minutes.
What time should I put an 18 lb turkey in for a 4 PM dinner?
By 11:00 AM: up to 4½ hours of roasting plus a 30-minute rest. Start checking the temperature at 3:15 PM.
How long does an 18 lb turkey take to thaw?
4–5 days in the fridge, or about 9 hours in cold water. For Thanksgiving 2026, move it to the fridge by Saturday, November 21.
How many people does an 18 lb turkey feed?
About 18 people, or 12 if you want leftovers.
Plan it in minutes
Type your 18 lb turkey and dinner time into the Thanksgiving Dinner Planner: you get the thaw date, oven time and a clock time for every side, plus the menu, shopping list and guest list.
See the Thanksgiving Dinner Planner →
