The Perfectly-Cooked Beef Tenderloin: How Long Should You Cook It at 250 Degrees?

We all love a good piece of beef tenderloin. When cooked right, it’s super tender, juicy, and absolutely delicious. But cooking tenderloin can be tricky. It’s an expensive cut of meat, so you don’t want to mess it up!

One of the most common ways to cook a beef tenderloin is to roast it in the oven at 250 degrees Fahrenheit. This low slow cooking method tenderizes the meat and gives you a nice even roast from the outside in. But exactly how long should you cook beef tenderloin at 250 degrees? That depends on a few factors.

In this article, I’ll walk you through everything you need to know to cook the perfect beef tenderloin in the oven at 250 degrees. We’ll cover:

• How long to cook a whole tenderloin roast
• Times for cooking tenderloin filets or medallions
• How oven temperature affects cooking time
• The best way to test for doneness
• Why resting time is so important
• Some additional oven-roasting tips for flawlessly-cooked beef

After reading this you’ll be able to roast beef tenderloin like a pro! Let’s get started.

How Long to Cook a Whole Tenderloin Roast at 250 Degrees

For a whole 3-5 pound beef tenderloin roast, you’ll want to cook it approximately 1-1 1/2 hours at 250 degrees F.

This will give you a perfect medium-rare interior while nicely browning the exterior. If you prefer your beef more done, add 5-15 minutes to get into the medium range.

Here are some more specific timelines based on tenderloin size:

• 3 pound tenderloin: Cook 1 hour 15 minutes (rare), up to 1 hour 30 minutes (medium)
• 4 pound tenderloin: Cook 1 hour 30 minutes (rare), up to 1 hour 45 minutes (medium)
• 5 pound tenderloin: Cook 1 hour 40 minutes (rare), up to 2 hours (medium)

The times above are for an untied, uncovered roast. If you tie your tenderloin into a uniform shape, it may cook slightly faster since it will heat more evenly. And if you cover it with foil at the start, it will likely need another 5-10 minutes.

No matter the size, always rely on a meat thermometer over cook times to gauge doneness. Ovens vary quite a bit, so cook times are just estimates. The thermometer reads the internal temp, so you’ll know exactly when it’s done. More on that shortly!

Cook Times for Tenderloin Filets and Medallions

For individual beef tenderloin filets or medallions, cook times will be much faster. Figure 3-5 ounces per filet, 1 1/2 – 2 inches thick.

At 250 degrees F, tenderloin filets will take approximately 15-25 minutes to reach medium-rare doneness.

For timing, think 5 minutes per ounce of meat. So a 4 ounce filet will take about 20 minutes, a 6 ounce filet around 30 minutes. Thicker cuts will need a bit more time.

You can monitor with a thermometer after the first 15 minutes of cooking and pull them when they’re 5-10 degrees below your target temp. They’ll continue cooking as they rest.

For very small tenderloin medallions, cut under 3 ounces, reduce cook times to just 10-15 minutes max. You want them still nice and juicy in the middle.

How Oven Temperature Affects Beef Tenderloin Cook Time

Cooking temperature makes a big impact on total roasting time. Here’s how oven temps of 250 F vs higher temps affect timing:

• 250 degrees F: Allows for slow, gradual cooking. Gives you the most hands-off cooking time.
• 275-300 degrees F: Reduces total cooking time by about 15-30 minutes.
• 325 degrees F and up: Cuts cooking time almost in half compared to 250 F. But harder to keep moisture in.

Lower temps around 250 degrees yield the most tender, juicy results. The meat has time to break down without overcooking the exterior.

Going over 325 degrees risks drying out the meat, so intermediate temps like 275 or 300 F are ideal for slightly faster cooking with moist, tender results.

Just remember to reduce the overall cooking time by about 15 minutes for every 25 degrees increased. And for very high oven temps above 400 F, watch the meat closely to avoid overcooking.

Use a Thermometer to Test Beef Tenderloin Doneness

A meat thermometer takes the guesswork out of determining doneness. Unlike appearance, touch, or cook time, it gives an exact internal temperature readout.

For medium-rare beef tenderloin, you’ll want to cook to an internal temp of 130-135 degrees F. 140 degrees F is more into the medium zone.

Always test temperature in the thickest part of the meat, avoiding bones or fatty areas. For whole tenderloin roasts, check the center and towards the ends which cook faster.

How to tell beef tenderloin doneness without a thermometer:

• Rare: Bright red center, cool inside
• Medium-rare: Warm red-pink center
• Medium: Hot pink center, firmer than rare/MR
• Medium-well: Trace of pink, pasty texture
• Well-done: No pink remaining, gray-brown throughout

But using a good digital instant read thermometer takes out the doubt! I recommend the Thermapen for quick accuracte readings.

Allow 10-15 Minutes Resting Time After Cooking

This last step is just as important as the cooking times! Allow your tenderloin roast or filets to rest for 10-15 minutes before slicing into them.

Resting gives the juices time redistribute through the meat after cooking. If you cut too soon, the juices spill out and you lose moisture, flavor, and tenderness.

During the resting period, the internal temperature will raise by about 5-10 degrees F. So pull roast and filets out of the oven when they’re 5 degrees below your desired final temp.

Tent them very loosely with foil as they rest to retain heat without fully trapping steam. The short steam bath helps keep them incredibly juicy.

Additional Oven-Roasting Tips for Perfect Beef Tenderloin

Here are a few more tips to ensure tender, juicy oven-roasted beef tenderloin every time:

• Pat the meat very dry before seasoning. This helps browning and creates a nice crust.
• Use a high heat oil like avocado, grapeseed, or rice bran to promote browning.
• Rub spices and oil all over before roasting. Herbs, salt, pepper, garlic, mustard, etc.
• Sear all sides in a skillet before roasting for enhanced flavor.
• Flip the roast halfway during cooking to evenly brown.
• Tent loosely with foil if browning too fast.
• Let rest on the counter, not back in a hot oven or it will overcook.

Master these simple steps along with the right cook times and temperatures, and you’ll be serving restaurant-worthy tenderloin in no time! Juicy, buttery-soft, with a nice browned crust.

For flavor variations, try different herb rubs or sauces like bernaise, chimichurri, or au poivre. And slice your rested roast nice and thick for the best texture.