Pork Loin Roast
at 375°F
1 hr 5 min – 1 hr 15 min Plan on 18 to 22 minutes per pound in a 375°F oven. A 3.5 lb pork loin roast lands around 1 hr 5 min – 1 hr 15 min. Done is 145°F on a food thermometer, plus a 10-minute rest — never the clock alone.
Time by weight at 375°F
Planning ranges for a fully thawed, fridge-temperature pork loin roast. The right-hand column is when to take the first thermometer reading.
| Weight | Estimated time at 375°F | Check thermometer from |
|---|---|---|
| 2 lb | 35 min – 45 min | 30 min in |
| 2.5 lb | 45 min – 55 min | 40 min in |
| 3 lb | 55 min – 1 hr 5 min | 45 min in |
| 3.5 lb | 1 hr 5 min – 1 hr 15 min | 55 min in |
| 4 lb | 1 hr 10 min – 1 hr 30 min | 1 hr in |
| 4.5 lb | 1 hr 20 min – 1 hr 40 min | 1 hr 10 min in |
| 5 lb | 1 hr 30 min – 1 hr 50 min | 1 hr 15 min in |
Start checking the internal temperature well before the low end of the range — an early check costs nothing; a late one costs the meal. Done means 145°F on a food thermometer.
375°F vs the other temperatures
Same cut, every temperature this site publishes for it.
| Oven temp | Time for a 3.5 lb pork loin roast | Per pound |
|---|---|---|
| 350°F | 1 hr 10 min – 1 hr 30 min | 20–25 min/lb |
| 375°F (this page) | 1 hr 5 min – 1 hr 15 min | 18–22 min/lb |
When is it actually done?
145°F internal The USDA FSIS safe minimum internal temperature for this cut is 145°F, followed by a rest of about 10 minutes. The clock estimates; the thermometer decides. Every time on this page is a planning range, not a doneness test.
Worth knowing before you start
- Loin is not shoulder: it is lean, cooks fast and dries out past 150°F. Pull at 140–143°F and let carry-over finish it at 145°F.
- The 145°F rule (with a 3-minute rest) replaced the old 160°F guidance in 2011 — pink-at-the-centre pork loin is correct, not undercooked.
- Fat cap up, so it bastes the roast as it renders.
Answers people ask
How long does a pork loin roast take at 375°F?
Plan on 18 to 22 minutes per pound at 375°F. A 3.5 lb example takes about 1 hr 5 min – 1 hr 15 min. It is done when the internal temperature reaches 145°F on a food thermometer, not when the clock runs out.
What internal temperature is a pork loin roast done at?
145°F, measured with a food thermometer in the thickest part, then rested about 10 minutes. That is the USDA FSIS safe minimum.
Is 375°F a good temperature for a pork loin roast?
It is one of 2 temperatures this site publishes for this cut (350°F, 375°F). Lower runs longer and more forgiving; higher runs faster with more browning. 350°F is the most common choice.
More pork timings
Pork Shoulder (Oven)
300°F · per-pound chart
Smoked Pork Butt
250°F · per-pound chart
Pork Tenderloin
400°F · 20 min – 25 min
Baby Back Ribs
250°F · 4 hr – 5 hr
Spare Ribs (St. Louis)
250°F · 4 hr 30 min – 5 hr 30 min
Ham (Fully Cooked, Bone-In)
325°F · per-pound chart
Fresh Ham (Uncooked)
325°F · per-pound chart
Where these numbers come from
Ranges are anchored to USDA FSIS published timetables where they exist, and derived from that anchor plus cross-checked published sources where they do not — widened to cover the disagreement between sources rather than split down the middle. The full reasoning is on the method page. If a figure here looks wrong, say so — corrections are prioritised.