How to Cook Costco Tri Tip Perfectly

What Is Costco Tri Tip?

Costco tri tip is a boneless beef cut from the bottom sirloin. It comes in a triangular shape and typically weighs between 2 to 3 pounds.

You’ll find it in the meat department, sold as either USDA Choice or USDA Prime grade. Costco also carries a Kirkland Signature pre-seasoned version if you want to skip the prep work.

This cut became popular in the Santa Maria Valley of California back in the 1950s. It cooks like a steak but feeds a small crowd. One roast serves 4 to 6 people.

Most home cooks pick tri tip for weeknight dinners because it cooks faster than brisket. You’re looking at 20 minutes in an air fryer, 30 minutes in the oven, or about 2 hours if you want that low and slow smoke ring.

This guide covers four cooking methods with exact temperatures and times.

Product Details

Product: USDA Choice/Prime Beef Loin Tri Tip Roast

Type: Fresh, raw beef roast (also available pre-seasoned)

Package Size: 2-3 lbs per roast (serves 4-6)

Price: $7.99-$9.99/lb at Costco (Updated January 2026)

Storage: Refrigerate at 40F or below; use within 3-5 days

Calories per Serving: 180-220 per 3oz cooked

Main Ingredients: Beef bottom sirloin

Item Number: Varies by location (check meat department)

Cooking Methods Comparison

Recommended Method: Air fryer for fastest cook time with a crispy seasoning crust and juicy texture throughout.

Method 1: Air Fryer (Recommended)

Air frying tri tip takes 16-20 minutes at 400F. You get a crispy exterior with a medium rare center. Works for 1.5-2 lb roasts that fit in a standard basket.

Step 1: How Do You Prepare Tri Tip for Air Frying?

Let the meat reach room temperature before cooking. This takes about 30 minutes on the counter.

Instructions:

1. Remove tri tip from packaging and pat dry with paper towels
2. Let rest at room temperature for 30 minutes
3. Coat all sides with 1 tablespoon olive oil
4. Apply dry rub seasoning generously (salt, pepper, garlic powder)

Equipment: Paper towels, olive oil, meat thermometer, air fryer basket

Step 2: What Temperature and Time Do You Use?

Preheat your air fryer to 400F for 5 minutes. Cook the roast for 8 minutes per side.

Instructions:

1. Preheat air fryer to 400F
2. Place seasoned tri tip in basket
3. Cook first side for 8 minutes

Temperature: 400F

Time: 16-20 minutes total

Step 3: When Do You Flip the Tri Tip?

Flip once at the halfway mark. Check internal temp after the second side finishes.

Instructions:

1. Flip tri tip at 8-minute mark using tongs
2. Cook second side for 8 minutes
3. Check temperature with instant read thermometer

Checkpoint: At 8-minute mark, flip and continue

Step 4: How Do You Know When It’s Done?

Use a meat thermometer inserted into the thickest part. Pull it out 5 degrees before your target because carryover cooking continues during rest.

Instructions:

1. Check internal temperature at thickest section
2. Remove at 125F for medium rare (will rise to 130-135F)
3. Tent with aluminum foil and rest 10 minutes

Target Temperature: 130-135F for medium rare

Visual Indicator: Browned crust with slight char on edges

Method 2: Oven Roasting

Oven roasting gives you even heat distribution. Start with a hot sear in a cast iron skillet, then finish in the oven at 425F for 25-30 minutes.

Step 1: How Do You Prepare Tri Tip for Oven Cooking?

Season the meat and let it warm up while your oven preheats.

Instructions:

1. Remove from fridge 45-60 minutes before cooking
2. Season with your beef rub blend on all sides
3. Preheat oven to 425F
4. Heat cast iron skillet on stovetop over high heat

Equipment: Cast iron skillet, roasting rack, meat thermometer

Step 2: What Temperature and Time Do You Use?

Sear first, then roast. The sear locks in flavor while oven heat cooks through evenly.

Instructions:

1. Sear tri tip 2-3 minutes per side in hot skillet
2. Transfer to oven on a rack
3. Roast at 425F for 20-25 minutes

Temperature: 425F oven

Time: 25-35 minutes total (including sear)

Step 3: When Do You Check the Roast?

Start checking temperature at 20 minutes. Every tri tip cooks a bit different based on thickness.

Instructions:

1. Insert thermometer at 20-minute mark
2. Check every 5 minutes until target temp

Checkpoint: At 20 minutes, begin monitoring

Step 4: How Do You Know When It’s Done?

Look for 125-130F internal temperature before removing. The roast keeps cooking as it rests.

Instructions:

1. Remove at 125F for medium rare doneness
2. Tent with foil on cutting board
3. Rest 10-15 minutes before slicing

Target Temperature: 130-135F after resting

Visual Indicator: Golden brown exterior, pink center when sliced

Method 3: Grilling

Grilling is the traditional Santa Maria style method. Use direct heat for searing, then move to indirect heat to finish. Total grill time runs about 25-30 minutes.

Step 1: How Do You Prepare Tri Tip for Grilling?

Season simply with salt, pepper, and garlic. Oak wood chips add authentic California flavor if you have them.

Instructions:

1. Bring meat to room temperature (30-45 minutes)
2. Pat dry and season all surfaces
3. Preheat grill to high heat (450-500F) on one side
4. Leave other side unlit for indirect cooking

Equipment: Gas or charcoal grill, tongs, meat thermometer

Step 2: What Temperature and Time Do You Use?

Start hot for sear marks. Then drop to indirect heat around 350F to finish without burning.

Instructions:

1. Sear over direct high heat 2-3 minutes per side
2. Move to indirect heat zone
3. Close lid and cook 20-25 minutes

Temperature: 450-500F direct, then 350F indirect

Time: 25-30 minutes total

Step 3: When Do You Flip During Grilling?

Flip once during the sear phase. After moving to indirect heat, no more flipping needed.

Instructions:

1. Sear first side 2-3 minutes until grill marks form
2. Flip and sear second side
3. Move to cool zone, fat cap up

Checkpoint: Check temp at 15 minutes on indirect heat

Step 4: How Do You Know When It’s Done?

Same target temp applies. Pull at 125F and let carryover cooking do the rest.

Instructions:

1. Check internal temp in thickest part
2. Remove when thermometer reads 125F
3. Rest 10-15 minutes under foil tent

Target Temperature: 130-135F for medium rare

Visual Indicator: Dark sear marks, slightly charred edges

Method 4: Smoker (Reverse Sear)

Smoking tri tip low and slow gives you that smoke ring and deeper beef flavor. Plan for 2 hours of smoking at 225F, followed by a quick sear. This reverse sear method is worth the wait.

Step 1: How Do You Prepare Tri Tip for Smoking?

A simple dry rub works. Let the seasoning sit on the meat for at least 30 minutes before smoking.

Instructions:

1. Apply dry rub seasoning (salt, pepper, garlic powder)
2. Let rest 30-60 minutes at room temperature
3. Preheat smoker to 225F
4. Use oak or hickory wood chips for best flavor

Equipment: Pellet grill or smoker, wood chips, meat thermometer, cast iron for searing

Step 2: What Temperature and Time Do You Use?

Low temperature smoking takes patience. The payoff is tender meat with real smoke flavor.

Instructions:

1. Place tri tip directly on grill grates
2. Smoke at 225F for approximately 2 hours
3. Target internal temp of 115-120F before searing

Temperature: 225F smoker setting

Time: 2-2.5 hours smoking, plus 5-6 minutes searing

Step 3: When Do You Sear After Smoking?

Pull the roast when it hits 115-120F internal. Sear immediately in a screaming hot cast iron skillet.

Instructions:

1. Heat cast iron to very high heat with butter
2. Sear each side 60-90 seconds
3. Garlic butter baste while searing

Checkpoint: At 115-120F, remove for searing

Step 4: How Do You Know When It’s Done?

The sear brings internal temp up to your target. Rest before slicing against the grain.

Instructions:

1. Sear until internal temp reaches 130F
2. Transfer to cutting board
3. Rest 15 minutes wrapped loosely in foil

Target Temperature: 130-135F for medium rare

Visual Indicator: Pink smoke ring visible when sliced, dark crusty exterior

Safety and Quality Indicators

Food Safety

• Internal Temperature: USDA recommends 145F minimum for beef roasts
• Medium Rare: 130-135F is safe when seared on outside
• Resting: Always rest meat before slicing to redistribute juices

Quality Indicators (Done Properly)

• Color: Deep brown crust with pink or red center
• Texture: Tender when sliced thin against the grain
• Temperature: Hot throughout, reaching target doneness
• Appearance: Juices run clear to slightly pink

Signs of Overcooking

• Gray color throughout with no pink
• Dry, tough texture even after resting
• Internal temperature exceeds 160F

Serving Suggestions

Portion Size: 4-6 oz cooked meat per person (6 servings per 2 lb roast)

Serving Ideas

• Slice thin and serve with chimichurri sauce
• Stack on crusty bread for tri tip sandwiches
• Cut into strips for tacos or fajitas
• Serve alongside Costco mashed potatoes for a classic dinner

Pairing Recommendations

• Costco jasmine rice as a simple side
• Costco frozen vegetables roasted alongside
• Red wine like Cabernet Sauvignon or Zinfandel

Storage and Reheating

Leftover Storage

• Refrigerate within 2 hours of cooking
• Store in airtight container
• Consume within 3-4 days
• Freeze for up to 3 months

Reheating Instructions

• Oven: 275F for 10-15 minutes until warmed through
• Skillet: Medium heat with butter, 2-3 minutes per side
• Target Temperature: 130-140F when reheating

Avoid microwaving if possible. It tends to make the meat rubbery.

Troubleshooting Common Issues

Issue: Tri tip is tough and chewy

Cause: Sliced with the grain instead of against it, or overcooked

Solution: Always identify the grain direction and slice perpendicular to the muscle fibers. For overcooked meat, slice extra thin.

Issue: Undercooked in the center

Cause: Started with cold meat or used too high heat without indirect cooking

Solution: Let meat reach room temperature before cooking. Use a two-zone heat method (sear then indirect) for even cooking.

Issue: Dry texture with no juice

Cause: Cooked past medium, or sliced too soon without resting

Solution: Pull meat at 125F and rest for 10-15 minutes minimum. The resting time lets juices redistribute throughout the roast.

Issue: Uneven cooking (one end overdone)

Cause: Tri tip has varying thickness due to its triangular shape

Solution: Position thicker end toward heat source. Consider cutting in half if thickness varies dramatically.

Product Variations and Related Items

Similar Costco Beef Products

• Costco brisket for longer smoking sessions
• Costco prime beef for upgraded marbling
• Costco short ribs for a different braising experience
• Costco burgers when you want something faster

Cooking Time Adjustments

• Smaller 1.5 lb roast: Reduce cook time by 5-8 minutes
• Larger 3 lb roast: Add 8-10 minutes, check temp frequently
• Pre-seasoned Kirkland version: No additional prep needed, same cook times apply

Which Method Should You Choose?

Choose Air Fryer when:

• You want dinner in under 30 minutes
• Cooking for 2-4 people
• You want a crispy crust without outdoor grilling

Choose Oven when:

• Weather keeps you inside
• You want consistent, predictable results
• Cooking a larger 3 lb roast

Choose Grill when:

• You want that traditional Santa Maria style flavor
• Cooking for a crowd outdoors
• Sear marks matter to you

Choose Smoker when:

• You have 2+ hours to spare
• Deep smoke flavor is the goal
• You want to impress with a smoke ring

Time Comparison

Air Fryer (16-20 min) < Oven (25-35 min) < Grill (25-30 min) < Smoker (2+ hours)

Texture Ranking

Smoker (most tender) > Grill (smoky char) > Air Fryer (crispy crust) > Oven (even browning)

FAQ on How To Cook Costco Tri Tip

What internal temperature should Costco tri tip reach?

For medium rare doneness, pull your tri tip at 130-135F. Medium runs 140-145F.

Use an instant read thermometer inserted into the thickest part. Always account for carryover cooking during rest time.

How long does it take to cook tri tip in the oven?

A 2 lb beef tri tip roast takes 25-35 minutes at 425F after searing.

Thickness matters more than weight. Start checking internal temperature at 20 minutes and monitor from there.

Should I marinate Costco tri tip before cooking?

Marinating is optional. Tri tip has enough natural beef flavor that a simple dry rub seasoning works great.

If you marinate, keep it under 4 hours. Longer breaks down the meat fibers too much.

What is the best seasoning for tri tip?

Santa Maria style uses salt, black pepper, and garlic powder. That’s it.

Some add paprika or onion powder. The Kirkland Signature pre-seasoned version saves prep time if you prefer convenience.

How do I slice tri tip correctly?

Always slice against the grain. The grain direction changes partway through this triangular cut.

Cut the roast in half first. Then slice each section perpendicular to the muscle fibers for tender results.

Can I cook frozen tri tip without thawing?

Not recommended. Frozen meat cooks unevenly and won’t develop a proper sear.

Thaw in the refrigerator for 24-48 hours. Then bring to room temperature for 30-45 minutes before cooking.

What is the difference between Choice and Prime tri tip at Costco?

USDA Prime has more marbling than USDA Choice. More fat means more flavor and tenderness.

Prime costs about $1-2 more per pound. Both grades cook the same way with identical times.

How long should tri tip rest before cutting?

Rest for 10-15 minutes minimum. Tent loosely with aluminum foil to retain heat.

Resting lets juices redistribute throughout the roast. Skip this step and you’ll lose moisture on the cutting board.

Why is my tri tip tough and chewy?

Two common causes. You sliced with the grain instead of against it. Or you overcooked past medium.

Check your meat thermometer next time. Pull at 125-130F and let carryover cooking finish the job.

Can I cook Costco tri tip in an air fryer?

Yes. Air fryer tri tip works great at 400F for 16-20 minutes total.

Flip once halfway through. The hot circulating air creates a crispy crust while keeping the center juicy and tender.

Conclusion

Learning how to cook Costco tri tip opens up a versatile weeknight dinner option. This bottom sirloin cut delivers big beef flavor without the long cook times of brisket.

Whether you use a pellet grill, Weber, or your kitchen oven, the key stays the same. Hit 130-135F for that perfect medium rare center.

Trim the fat cap if needed. Season simply. Let it rest before you slice.

Your Traeger or air fryer will handle the rest. Now go cook one.