Skirt steak comes from the cow’s plate section, on the underside of the chest and belly area below the ribs. It’s a long, thin diaphragm muscle; cook beef steaks to 145°F and let rest 3 minutes.
What Part Of The Cow Does Skirt Steak Come From: 1 plate primal, the lower chest and belly of the cow, just under the ribs. It is a long, flat cut from the diaphragm area, prized for big beef taste and quick cooking.
There are 2 skirt steaks: outside skirt and inside skirt. Outside skirt sits on the outer chest wall and is often more tender. Inside skirt lies deeper in the body wall. Cook beef steak cuts to 145°F and rest 3 minutes.
Straight To The Numbers
Skirt steak comes from the cow’s plate section, on the underside of the animal, below the ribs and near the belly. It is the diaphragm muscle, not a leg, loin, rib, or round cut.
There are 2 skirt steaks per cow: 1 outside skirt and 1 inside skirt. Both are long, flat, coarse-grained muscles from the plate area, but they are not identical cuts.
Where It Sits On The Cow
Think of the cow divided into major butcher sections. Skirt steak is from the plate, which sits under the rib primal and in front of the flank. It is low on the animal, along the belly-side wall.
The outside skirt is the diaphragm muscle attached to the inside of the chest wall. The inside skirt is from the transversus abdominis area, also on the inner body wall.
In plain kitchen terms: skirt steak is a belly-side, plate-section steak with very visible grain. It is not flank steak, though both are flat, beefy, and often used for fajitas.
| Relevant USDA/FDA row | Safe minimum internal temperature | Rest time | How it applies to skirt steak |
|---|---|---|---|
| Beef, pork, veal and lamb – steaks, chops, roasts | 145°F (63°C) | 3 minutes | Use for whole skirt steak cooked as a steak |
| Leftovers, reheated | 165°F (74°C) | None | Use for reheating cooked skirt steak |
Outside Skirt Vs Inside Skirt
Outside skirt is usually the more prized piece. It tends to be thicker, more uniform, and more tender. Butchers often sell it to restaurants, so shoppers more often see inside skirt at retail.
Inside skirt is usually wider and thinner. It can be slightly tougher, but it has the same bold beef flavor and the same long muscle fibers. Slice it correctly and it eats well.
A typical skirt steak is long and narrow. Instead of cutting with the length of the strip, cut across the grain. If the grain runs left to right, your knife cuts up and down.
Worked example: if a skirt steak is 18 inches long, cut it into 3 shorter pieces of about 6 inches each before cooking. After cooking, rotate each piece and slice across the grain.
That 2-step cut matters because the grain can run the full length of the steak. Shortening a 6-inch fiber into thin cross-grain slices gives a much more tender bite.
Cooking Numbers That Matter
For whole skirt steak, the relevant safe minimum internal temperature is 145°F, followed by a 3-minute rest. Measure the thickest part with a food thermometer.
Edge case: if cooked skirt steak is later reheated as leftovers, the relevant number changes to 165°F with no rest time listed. That is for reheating leftovers, not for the first cook.
Another edge case: if skirt steak is chopped and mixed into a meat casserole, do not use the steak row. Use the applicable casserole rule only when the dish is a casserole containing meat or poultry.
The key answer remains simple: skirt steak is from the plate, specifically diaphragm-area muscle on the cow’s underside. A cow provides 2 skirt steaks, outside and inside, both cut from that lower body wall.
Where Skirt Steak Comes From
Skirt steak comes from the cow’s plate, the lower chest and belly area directly below the rib primal. It is not a loin steak. It is a long, flat diaphragm-area muscle with coarse grain and strong beef flavor.
There are 2 skirt steaks on each beef carcass side: the outside skirt and the inside skirt. A whole animal has 4 skirt steaks total, 2 outside and 2 inside.
Exact Location On The Cow
- 1. Start at the rib cage: Find the lower half of the ribs, beneath the ribeye section. Skirt steak sits on the underside of this area, not on top of the back.
- 2. Move to the plate primal: The plate is below the ribs and ahead of the flank. This is the main butcher area associated with skirt steak.
- 3. Identify the diaphragm area: The outside skirt is the diaphragm muscle. It lies against the inside of the chest wall and is the rarer, thicker skirt.
- 4. Find the inside skirt: The inside skirt is located farther inside the body wall, below and behind the ribs. It is longer, wider, and usually thinner than outside skirt.
- 5. Separate it from flank steak: Flank steak comes from the abdominal flank, behind the plate. Skirt steak comes farther forward, from the plate and diaphragm region.
- 6. Trim the membranes: Skirt has tough surface membrane and visible long fibers. Butchers remove the heavy membrane, then leave a flat strip ready for slicing or marinating.
A typical outside skirt is about 20 to 24 inches long and 3 to 4 inches wide. It is usually thicker than inside skirt and often weighs around 1 to 2 pounds after trimming.
A typical inside skirt can run about 20 to 28 inches long and 4 to 7 inches wide. It is usually thinner and may look more ragged along the edges.
Worked example: if a butcher breaks down one steer, expect 2 outside skirts and 2 inside skirts. If each trimmed skirt averages 1.5 pounds, the whole animal yields about 6 pounds of skirt steak.
That small yield explains why skirt steak can be expensive. A 1,200-pound steer does not produce dozens of skirt steaks; it produces only 4 true skirt muscles.
The grain is the easiest visual clue. Skirt steak has thick, rope-like fibers running across the short width or length of the strip. Those fibers are much more obvious than on sirloin or ribeye.
Edge case: “fajita meat” is often skirt steak, but not always. Some stores use flap meat, sirloin flap, or flank. If the label does not say “skirt,” it may not be from the plate.
Another edge case is “outer skirt.” That means outside skirt, the diaphragm muscle. It is prized by restaurants because it is thicker, more uniform, and especially beefy.
“Inner skirt” means inside skirt. It is still real skirt steak, but it is usually thinner and less even. It benefits from careful trimming and slicing across the grain.
For doneness, skirt steak is beef steak. The USDA safe minimum for beef steaks is 145°F with a 3-minute rest.
Inside Versus Outside Skirt
Skirt steak comes from the cow’s plate section, low on the belly, just behind the brisket and below the ribs. The 2 market cuts are inside skirt and outside skirt, and they are different muscles.
Outside skirt is the diaphragm muscle. Inside skirt is the transversus abdominis muscle, part of the abdominal wall. Both are long, flat, coarse-grained cuts, but they do not cook or trim exactly alike.
Where Each Skirt Sits On The Cow
Outside skirt lies on the outside of the chest wall, attached to the rib area by a tough membrane. There are 2 outside skirts per beef carcass, 1 from each side.
Inside skirt sits farther inside the body wall, running along the belly side of the plate. There are also 2 inside skirts per carcass, but they are usually wider, thinner, and less uniform.
| Cut | Muscle | Typical Shape | Common Weight |
|---|---|---|---|
| Outside skirt | Diaphragm | Long, narrow, thicker | About 1 to 2 lb |
| Inside skirt | Transversus abdominis | Long, wider, thinner | About 1.5 to 2.5 lb |
Outside skirt is usually the more prized cut. It has a beefier flavor, a looser grain, and more even thickness. Restaurants often buy much of the supply, which is why grocery cases more often show inside skirt.
Inside skirt is still true skirt steak, not a substitute cut. It is usually chewier because it is thinner, broader, and has more connective tissue running through the sheet of meat.
How To Tell Them Apart At The Store
Outside skirt is commonly 3 to 4 inches wide and may be 20 to 24 inches long. It looks like a narrow belt of meat. The grain is bold, and the strip often has a more rounded thickness.
Inside skirt may be 5 to 7 inches wide and can look flatter and more ragged. If a package is broad, thin, and folds over itself, it is more likely inside skirt.
Labels are not always precise. “Skirt steak” without “outside” usually means inside skirt in many retail cases. If the label says “outside skirt,” expect a higher price and a smaller, neater piece.
Worked Example: Buying For Fajitas
For 4 servings at 6 oz raw beef per person, buy 24 oz, or 1.5 lb, of skirt steak. If using inside skirt with heavy membrane or surface fat, buy closer to 1.75 lb.
For 6 servings, plan 36 oz, or 2.25 lb, raw. That may be 1 large inside skirt or 2 smaller outside skirts. Cut long pieces into 6- to 8-inch sections before cooking for easier handling.
Slice both cuts across the grain, not with it. On skirt steak, the grain usually runs across the short width. Turn the cooked strip so your knife cuts the visible fibers into short pieces.
For safety, USDA lists beef steaks at 145°F with a 3-minute rest. Use a thermometer in the thickest part, especially with outside skirt, because it can be thicker than inside skirt.
How Butchers Remove Skirt Steak
Skirt steak is removed from the plate section, on the underside of the cow, below the ribs and near the belly. Butchers separate 2 different muscles: the outside skirt and the inside skirt.
The outside skirt is the diaphragm muscle. It sits against the inside of the chest wall, attached near ribs 6 through 12. It is usually the thicker, more prized skirt, but each cow has only 2 outside skirts.
The inside skirt comes from the transversus abdominis muscle. It lies farther inside the plate, running along the lower belly. It is longer and usually wider, but often thinner and looser-grained.
Step-by-step removal
First, the butcher breaks the carcass into primal sections. Skirt steak is handled when the plate is separated from the rib and brisket areas. The plate contains the lower rib bones, cartilage, fat, and belly muscles.
For outside skirt, the butcher works along the inner rib cage. The knife follows the membrane where the diaphragm is attached, keeping the blade almost flat to avoid gouging the meat.
An outside skirt is often about 20 to 24 inches long and 3 to 5 inches wide. After trimming, many pieces weigh about 1 to 2 pounds, depending on cattle size and trim level.
For inside skirt, the butcher removes a longer belly muscle from the inner plate. It may run 20 to 30 inches and can be 5 to 7 inches wide before trimming.
The key cut is not a deep chop. It is a peeling cut. The butcher lifts one edge of the muscle, then uses short strokes to free it from membrane, fat seams, and connective tissue.
Trimming, membrane, and yield
Skirt steak has a heavy membrane on one or both sides. Butchers usually pull or slice away the thick silver skin because it shrinks, curls, and turns chewy when cooked.
On a 2.25-pound untrimmed outside skirt, a realistic trim loss may be 6 to 10 ounces. That leaves about 1.6 to 1.9 pounds of usable steak.
Inside skirt can lose more if it carries thick fat and ragged edges. For example, a 3-pound inside skirt may trim down to 2.2 to 2.5 pounds after membrane and excess fat are removed.
Butchers trim differently for retail and restaurants. Retail skirt is often cleaned more closely. Restaurant skirt may keep a little fat because cooks can trim again after portioning.
A common portioning example is simple: a 1.8-pound trimmed outside skirt equals 28.8 ounces. Cut into 6 portions, each piece is about 4.8 ounces before cooking.
Edge cases butchers watch for
Outside skirt is limited. Since each animal has only 2, a meat case may label inside skirt simply as “skirt steak” when outside skirt is unavailable.
If the steak is unusually wide, flat, and thin, it is often inside skirt. If it is narrower, thicker, and more uniform, it is more likely outside skirt.
Some skirt pieces look ragged because the butcher followed natural seams instead of cutting a perfect rectangle. That is normal and can preserve more meat.
If a “skirt steak” is very thick and steak-shaped, it may be flap meat or hanger steak mislabeled. True skirt has long muscle fibers running clearly across the width.
For food safety, beef steaks, chops, and roasts have a safe minimum internal temperature of 145°F, followed by a 3-minute rest.
Why This Cut Is Thin
Skirt steak is thin because it is cut from the cow’s diaphragm muscles, not from a thick round or loin muscle. These muscles sit as long, flat sheets inside the plate section, below the ribs and toward the belly.
A typical skirt steak is only about 1/2 to 3/4 inch thick, but it can be 20 to 24 inches long. Its shape comes from anatomy: the muscle is built like a strap that helps the animal breathe.
Inside Skirt vs. Outside Skirt
There are 2 skirt steaks on each side of beef: inside skirt and outside skirt. Both are diaphragm-related cuts, but they differ in size, thickness, grain, and tenderness.
| Cut | Where it sits | Typical shape | Eating quality |
|---|---|---|---|
| Outside skirt | Outer diaphragm area, attached near ribs | Longer, wider, often thicker | More tender, prized for steak use |
| Inside skirt | Inner plate, farther inside the body cavity | Long, narrow, flatter | Chewier, still flavorful |
The outside skirt is usually the more desirable piece because it is thicker and more uniform. The inside skirt is commonly thinner, more irregular, and easier to overcook at the narrow ends.
Think of the cut as a flat belt of muscle. If a piece is 22 inches long, 4 inches wide, and 1/2 inch thick, it has a large surface area but little depth. Heat reaches the center fast.
That geometry explains why skirt steak cooks so quickly. A 1/2-inch skirt steak may move from seared to overdone in minutes, especially over high heat or in a hot cast-iron pan.
Why the Grain Looks So Bold
Skirt steak looks striped because the muscle fibers run in thick, visible bundles across the cut. The cow uses these diaphragm muscles constantly for breathing, so the fibers are strong.
Thinness does not mean tenderness. A thin inside skirt can still chew tough if sliced with the grain. Cut it into 3- to 4-inch sections first, then slice each section across the grain.
Worked example: if a skirt steak is 18 inches long and the grain runs lengthwise, do not carve 18-inch strips. Cut it into 4 pieces about 4 1/2 inches long, then slice each piece crosswise.
Edge Cases at the Meat Counter
If the steak is labeled “skirt” but looks very thick, short, and blocky, it may be mislabeled or folded. True skirt should look flat, fibrous, and strap-like, not like a compact sirloin steak.
If one end is 3/4 inch thick and the other is 1/4 inch thick, cook for the thick end and expect the thin end to be more done. You can also trim the thin flap off and cook it separately.
For safety, beef steaks, chops, and roasts have a safe minimum internal temperature of 145°F with a 3-minute rest. Use a thermometer in the thickest section, not the tapered tip.
The short answer: skirt steak is thin because it comes from a long diaphragm muscle in the plate, built as a flat working sheet rather than a thick storage muscle.
Cuts Often Confused With Skirt
Skirt steak is often mixed up with flank, hanger, flap, and flat iron because all 5 are thin, beefy cuts used for fajitas, tacos, stir-fries, or quick grilling.
The fastest ID check is grain, shape, and source. Skirt comes from the plate, below the ribs. It is long, narrow, loose-grained, and usually 3 to 4 inches wide.
Skirt vs Flank Steak
Flank steak comes from the abdominal area, not the plate. It is usually wider, flatter, and more even than skirt, often about 8 to 12 inches wide and 1 to 2 pounds per piece.
Skirt has thick, rope-like muscle fibers running across its width. Flank has tighter, straighter grain running lengthwise. If the piece looks like a broad rectangle, it is probably flank.
Worked example: a 1.5 lb steak that is 10 inches wide, 14 inches long, and evenly 3/4 inch thick is flank, not skirt. A 1.5 lb piece that is 4 inches wide and 24 inches long points to skirt.
Cooking overlap causes confusion. Both are best sliced across the grain. For beef steaks, the safe minimum internal temperature is 145°F with a 3-minute rest.
Skirt vs Hanger Steak
Hanger steak comes from the diaphragm area, but it is not the same cut as skirt. It hangs near the kidney and is usually sold as 1 thick, central piece rather than a long ribbon.
A hanger steak often has a tough membrane down the middle. Butchers may split it into 2 lobes. Skirt does not have that central seam; it is flatter and more strap-like.
Edge case: an “onglet” on a menu is hanger, not skirt. If a butcher says the cut has only 1 per animal in a paired lobe shape, that is hanger. Skirt comes as inside and outside skirt.
Skirt vs Flap Meat
Flap meat, also called bavette or sirloin flap, comes from the bottom sirloin. It has a coarse grain like skirt, so it is one of the most common substitutes.
The key difference is size and thickness. Flap is usually chunkier and more triangular or irregular. Skirt is thinner, longer, and more uniform, often trimmed into strips for marinating.
Example: if a package labeled “skirt” contains 2 thick, broad pieces totaling 2.5 lb with uneven triangular ends, check the fine print. It may be flap meat sold as a fajita-style substitute.
Skirt vs Flat Iron
Flat iron comes from the shoulder, specifically the chuck area. It is tender and rectangular, with a finer texture than skirt. It does not have skirt’s obvious rope-like grain.
Flat iron is usually thicker, often around 1 inch, and looks like a neat steakhouse portion. Skirt is thinner and longer, commonly folded in the package because it may exceed 18 inches.
If you need true skirt for fajitas, ask for “outside skirt” or “inside skirt” from the plate. If the label says chuck, shoulder, top blade, or flat iron, it is not skirt steak.
| Cut | Usual clue | Notable difference from skirt |
|---|---|---|
| Flank | Wide rectangle | Tighter grain, from abdomen |
| Hanger | Thick lobes | Central seam, not a long ribbon |
| Flap | Coarse, irregular slab | From bottom sirloin |
| Flat iron | Neat thick rectangle | From chuck, finer texture |
What To Ask The Butcher
Ask for “skirt steak from the plate,” the diaphragm area under the ribs. Then ask whether it is outside skirt or inside skirt; they cook similarly, but outside skirt is usually thicker, more tender, and in shorter supply.
Key Questions At The Counter
Ask: “Is this outside skirt or inside skirt?” Outside skirt has a looser grain and a meatier bite. Inside skirt is wider, thinner, and benefits from marinade and fast cooking.
Ask for the membrane to be removed. A trimmed skirt steak should still have visible grain, but no papery silver skin that tightens on the grill.
Ask for steaks about 1/2 to 3/4 inch thick. Thinner pieces can overcook in under 2 minutes per side on a hot grill.
For fajitas or tacos, plan 6 to 8 ounces raw skirt steak per adult. Example: for 4 adults, buy 1 1/2 to 2 pounds raw.
If the butcher has only long strips, ask them not to cube it. Instead, have it left whole or cut into 6- to 8-inch sections so you can slice across the grain after cooking.
Ask when it was cut. For best texture, use fresh skirt steak within 1 to 2 days, or freeze it tightly wrapped if you are not cooking it soon.
Labeling Terms At The Meat Counter
“Skirt steak” should mean a long, flat beef cut from the plate area, below the ribs. At retail, the key words are “inside skirt” and “outside skirt,” because they are not the same muscle.
Inside Skirt Vs. Outside Skirt
Outside skirt is the diaphragm muscle. In meat-buyer specs, it is IMPS/NAMP 121C. It is usually wider, thicker, and more uniform than inside skirt.
Inside skirt is IMPS/NAMP 121D. It comes from the inside wall of the chest and abdomen area. It is often thinner and less even, but it is still labeled and sold as skirt steak.
Worked Label Example
If a package says “Beef Outside Skirt Steak, 1.25 lb,” you are buying the 121C cut. At $15.99 per lb, the package cost is 1.25 × 15.99 = $19.99 before tax.
If the label only says “skirt steak,” ask whether it is inside or outside. For fajitas, either works, but outside skirt is commonly prized for its texture and shape.
Do not confuse skirt with flank steak. Flank comes from the flank primal, not the plate, and is a different single muscle even though both are long-grained cuts.
Sources We Checked
Reader Questions
What part of the cow does skirt steak come from?
Skirt steak comes from the plate section of the cow, on the underside near the belly and ribs. It is the diaphragm muscle, so it is long, thin, and strongly grained. There are 2 skirt steaks per cow: inside skirt and outside skirt.
Is skirt steak the same as flank steak?
No. Skirt steak comes from the plate, while flank steak comes from the flank area farther back on the cow. Skirt steak is usually thinner, fattier, and more intensely beefy. Flank steak is wider, leaner, and often slightly easier to slice evenly.
What is the difference between inside skirt and outside skirt steak?
Outside skirt is from the outside of the chest wall and is usually thicker, more tender, and more uniform. Inside skirt is from the inner body wall and is often wider, thinner, and a bit tougher. Butchers often reserve outside skirt for restaurants.
Why is skirt steak so chewy?
Skirt steak is chewy because it is a working diaphragm muscle with long, visible fibers. The fix is to cook it hot and fast, then slice it across the grain. Cutting across those fibers can turn long chewy strands into short, tender bites.
What temperature should skirt steak be cooked to?
For beef steaks, including skirt steak, the USDA safe minimum internal temperature is 145°F followed by a 3-minute rest. Use an instant-read thermometer in the thickest part. Skirt steak is thin, so it can move from underdone to overdone quickly.
How should skirt steak be sliced after cooking?
Slice skirt steak across the grain, not with it. The muscle fibers run in long, visible lines, so turn the steak 90 degrees and cut thin strips, about 1/4 inch thick. This shortens the fibers and makes each bite noticeably more tender.
How long should you marinate skirt steak?
Marinate skirt steak for 30 minutes to 24 hours, depending on the marinade. Acidic marinades with lime juice, vinegar, or wine work best in shorter windows, around 30 minutes to 4 hours, because too much acid can make the surface mushy.
What is skirt steak best used for?
Skirt steak is best for quick, high-heat cooking and sliced dishes. It is commonly used for fajitas, tacos, steak salads, stir-fries, and sandwiches. Because it is thin, it often cooks in just a few minutes per side on a hot grill or skillet.
