Spare Ribs (St. Louis)
at 275°F
3 hr 30 min – 4 hr 30 min a Rack Of Spare Ribs take about 3 hr 30 min – 4 hr 30 min in a 275°F smoker. Done is 145°F on a food thermometer, plus a 10-minute rest — never the clock alone.
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.
Pull temperature vs safe temperature: Like baby backs, spares are done by feel around 190–203°F — the bend test and probe-tender between the bones — not at the 145°F safe minimum.
Sizing: Times are per rack (a St. Louis-trimmed rack runs ~2.5–3.5 lb; full spares slightly longer).
Worth knowing before you start
- Spares carry more fat and connective tissue than baby backs — they take about an hour longer and forgive more.
- St. Louis trim (square, brisket flap removed) cooks more evenly than an untrimmed full spare rack.
- The classic 3-2-1 wrap sequence was designed for exactly this cut at 225°F.
Answers people ask
How long does a rack of spare ribs take at 275°F?
About 3 hr 30 min – 4 hr 30 min at 275°F (times are per rack (a St. Louis-trimmed rack runs ~2.5–3.5 lb; full spares slightly longer).). It is done at 145°F internal on a food thermometer, not by the clock.
What internal temperature is a rack of spare ribs 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. Like baby backs, spares are done by feel around 190–203°F — the bend test and probe-tender between the bones — not at the 145°F safe minimum.
Is 275°F a good temperature for a rack of spare ribs?
It is one of 3 temperatures this site publishes for this cut (225°F, 250°F, 275°F). Lower runs longer and more forgiving; higher runs faster with more browning. 250°F is the most common choice.
More pork timings
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.