Fajita vs. Taco Seasoning: How Do They Compare?

Put the two packets side by side and the big difference is sourness: fajita seasoning carries lime or citric acid, and the taco packets we checked carry none.¹² Otherwise they share a core of chile, garlic, onion and salt. The packets are also built for different jobs. Taco mixes contain starch and call for 3/4 cup of water to make saucy ground meat,³ while a fajita packet goes on strips of meat with peppers and onions and only 1/4 cup of water.⁴ Either one can stand in for the other with a small fix.

Side by side

	Fajita seasoning	Taco seasoning
What it seasons	Strips of chicken or beef, cooked with onion and bell pepper	Ground meat for tacos
Federal purchasing specification	USDA has an entry, with a minimum ingredient list¹	No entry in the same specification¹
Ingredients, USDA minimum list	Salt, black pepper, cumin, oregano, garlic, onion, red pepper, natural lime flavor¹	None given
Ingredients, one packet label each	McCormick: spices (including chili pepper, cumin, paprika), garlic, salt, sugar, onion, corn starch, citric acid, lime juice concentrate⁴	McCormick Original: spices (including chili pepper, paprika, oregano), corn starch, salt, onion, garlic.² Old El Paso Gluten Free Original: corn starch first, then chili pepper, maltodextrin, salt, spice, onion powder and minor ingredients³
Sour element	Natural lime flavor (USDA); citric acid and lime juice concentrate (McCormick)¹⁴	None named on either label²³
Key compounds, by ingredient	Capsaicinoids from chile for heat;⁵ cuminaldehyde, 20–72% of cumin oil across studies;⁶ citric acid	Capsaicinoids from chile;⁵ carvacrol and thymol, about 78–85% of Origanum vulgare oil;⁷ the labels do not say which oregano
Sodium (label)	250 mg per 1 1/2 tsp; about 2,000 mg in a 1.12 oz packet by our arithmetic⁸	McCormick: 380 mg per 1 1/2 tsp, six servings, about 2,280 mg a packet.² Old El Paso: 280 mg per 2 tsp, five servings, 1,400 mg³
Packet directions	One packet, 1 lb chicken or sirloin in strips, onion, bell pepper, 1/4 cup water⁴	One packet, 1 lb ground meat, 3/4 cup water²³
Flavor	Chile and cumin first, garlic and onion behind, a tart lime edge	Rounder and more savory, chile and herb, no tartness, a thicker sauce
Where the dish comes from	Ranch lands of South and West Texas	Origins unknown, per historian Jeffrey Pilcher⁹
Cost	No dated, sourced comparison found	No dated, sourced comparison found

The label rows compare one or two products, not every brand. “Spices” on a label can cover ingredients that aren’t named, so a spice missing from a label doesn’t prove it’s absent.⁴²

The sour note

This is the one difference every source we checked agrees on. The USDA’s purchasing specification lists natural lime flavor among fajita seasoning’s minimum ingredients,¹ and McCormick’s fajita mix lists citric acid and lime juice concentrate.⁴ Neither taco label lists an acid.²³ The USDA’s minimum list for chili powder, which plenty of cooks use as a taco base, has no acid either: ground chili pepper, cumin, oregano, salt and garlic powder.

You’ll often read that the lime is there to copy a traditional lime marinade that tenderized tough skirt steak. Skirt steak is the original fajita cut, according to The Austin Chronicle’s history,¹⁰ but we found no source for the marinade tradition or the tenderizing claim. Tomato powder also gets called a souring agent in fajita blends, but no label we checked lists it. One homemade recipe does. PepperScale adds optional tomato powder to its fajita seasoning for color and a tang it likens to the lime in fajita marinades, and calls that the main thing separating its blend from taco seasoning, which it otherwise finds quite a bit alike.¹¹

Starch, water and what each packet is built for

Taco packets are thickened. Both labels list corn starch, and Old El Paso’s lists it first.²³ Cook’s Country, which built a homemade blend “designed and tested to replace” a packet, adds cornstarch because it gave the pan juices of ground beef a saucy body.¹² With 3/4 cup of water per pound, you get a loose, saucy filling.

The McCormick fajita mix has corn starch too, but its directions use only 1/4 cup of water for a pound of meat strips, stirred in with the meat at the end and cooked for about 3 minutes.⁴ America’s Test Kitchen’s skillet chicken fajitas skip the packet entirely: chili powder, cumin, salt and pepper on the chicken, and lime juice on the vegetables at the end.¹³

Cumin, oregano and chile

Both blends lean on the same chile flavor, but the labels name different supporting spices. McCormick’s fajita mix names cumin and paprika among its spices; its taco mix names paprika and oregano.⁴² The USDA fajita list includes both cumin and oregano,¹ and Cook’s Country’s taco blend uses cumin along with chili powder, paprika, garlic, onion and oregano.¹² So in practice, either can carry both. Neither label names cayenne.

Chile heat comes from capsaicinoids, but we didn’t find a published heat measurement for either blend. How hot a jar is depends on the brand.

Salt

Packet for packet, the salt is close. By the labels, McCormick’s taco packet carries about 2,280 mg of sodium and its fajita packet about 2,000 mg; Old El Paso’s taco packet carries 1,400 mg.³ The FDA’s Daily Value for sodium is less than 2,300 mg a day.¹⁴ Spoon for spoon, McCormick’s taco mix is saltier, at about 253 mg per teaspoon against about 167 mg for the fajita mix (our math from the labels).⁸²

Where the dishes come from

Virginia B. Wood’s history of fajitas in The Austin Chronicle, drawing on Homero Recio’s 1984 study, finds anecdotal evidence of fajitas going back to the 1930s in the ranch lands of South and West Texas, and the first commercial fajita taco stand in Kyle, Texas, in 1969.¹⁰ The taco is older and murkier. Historian Jeffrey M. Pilcher told Smithsonian Magazine that its origins are really unknown, and listed hamburger in place of offal among the changes in the American fast-food taco.⁹ We found no date for the first packaged taco or fajita seasoning. So “both have their origins in Mexican cuisine” is too simple: fajitas as a named dish trace to Texas.

Can one stand in for the other?

Yes. These come from our substitute pages.

Taco seasoning in place of fajita seasoning. Ratio (Computed): Packet for packet, the McCormick taco mix gives about 15% more sodium than the fajita mix, so use one for one. Spoon for spoon, use about two thirds as much. That’s label math, for salt only, for these products.⁸² Then add the sour note at the end with lime juice. ATK uses 4 teaspoons of lime juice for 12 to 16 ounces of chicken;¹³ that amount makes a good starting point with taco seasoning too. See fajita seasoning substitutes.
Fajita seasoning in place of taco seasoning. PepperScale calls its homemade fajita blend great as a taco seasoning substitute.¹¹ Ratio (Computed): The sodium is similar packet for packet,⁸² so swap one packet for one and skip any lime or vinegar the recipe adds. Expect tangier meat. If you want the saucy texture, a little cornstarch helps: Cook’s Country uses 2 teaspoons in its packet replacement.¹² See taco seasoning substitutes.

If a fajita blend makes your taco filling too tart, the easiest fix is to use less of it and make up the chile with plain chili powder.

Beyond tacos and fajitas

Fajita seasoning suits grilled fish, shrimp and chicken thighs, sheet-pan vegetables and rice, anywhere a tart edge helps. Taco seasoning suits chili, taco soup, beans and dry rubs.

Neither is a close stand-in for other all-purpose blends. Goya’s adobo lists salt, garlic, black pepper, oregano and turmeric, with no chile,¹⁵ and McCormick’s Cajun seasoning lists paprika, red pepper, thyme, black pepper and celery seed with garlic and onion.¹⁶ Swap a taco blend for either one and the dish changes noticeably.

Safety

Sodium. One taco packet can come close to a full day’s sodium Daily Value.²¹⁴
Chile spices. The EU sets maximum levels of ochratoxin A and aflatoxins for dried Capsicum spices, including chili powder and paprika,¹⁷ which covers the chile in both blends.

What isn’t known

No heat measurement exists for either blend.
Brands don’t publish their spice proportions, and labels lump some spices together as “spices.”
We couldn’t trace the lime-marinade origin of the sour note, and tomato powder shows up only in one homemade recipe, not on any commercial label we checked.¹¹
We found no date for the first commercial taco or fajita seasoning.

Commercial Item Description A-A-20001C, Spices and Spice Blends, USDA Agricultural Marketing Service, 2023. ams.usda.gov · Regulator ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷
McCormick Original Taco Seasoning Mix, ingredients, nutrition label and directions, via Giant Food Stores. giantfoodstores.com · Merchant ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹ ↩¹⁰ ↩¹¹ ↩¹² ↩¹³
Old El Paso Gluten Free Original Taco Seasoning Mix, ingredients, nutrition label and directions, via Giant Food Stores. giantfoodstores.com · Merchant ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸
McCormick Fajita Seasoning Mix, product page, McCormick. mccormick.com · Merchant ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸
Bosland and Walker, “Measuring Chile Pepper Heat”, New Mexico State University, 2010. pubs.nmsu.edu · Reference work ↩ ↩²
P.C.M. Jansen, Cuminum cyminum, Plant Resources of South-East Asia (PROSEA). uses.plantnet-project.org · Reference work ↩
Lombrea et al., “A Recent Insight Regarding the Phytochemistry and Bioactivity of Origanum vulgare L. Essential Oil”, International Journal of Molecular Sciences, 2020. mdpi.com · Peer-reviewed ↩
McCormick Fajita Seasoning Mix, 1.12 oz, ingredients and nutrition, via ShopRite. shoprite.com · Merchant ↩ ↩² ↩³ ↩⁴
Katy June Friesen, “Where Did the Taco Come From?”, Smithsonian Magazine, 2012. smithsonianmag.com · Publication ↩ ↩²
Virginia B. Wood, “Fajita History”, The Austin Chronicle, 2005. austinchronicle.com · Publication ↩ ↩²
Matt Bray, Homemade Fajita Seasoning, PepperScale, 2023. pepperscale.com · Publication · PepperScale is also owned by Matt Bray, the editor of this site. ↩ ↩² ↩³
Matthew Fairman, “Homemade Taco Seasoning”, Cook’s Country (America’s Test Kitchen), 2023. americastestkitchen.com · Publication ↩ ↩² ↩³
Weeknight Skillet Chicken Fajitas, America’s Test Kitchen, 2013. americastestkitchen.com · Publication ↩ ↩²
“Sodium in Your Diet”, U.S. Food and Drug Administration. fda.gov · Regulator ↩ ↩²
Goya Foods, Adobo All-Purpose Seasoning with Pepper, trade product page. trade.goya.com · Merchant ↩
McCormick Signature Seasonings Cajun, ingredients and nutrition label, via Giant Food Stores. giantfoodstores.com · Merchant ↩
Commission Regulation (EU) 2023/915 on maximum levels for certain contaminants in food, EUR-Lex. eur-lex.europa.eu · Regulator ↩

Fajita vs. Taco Seasoning: The Sour Note, the Starch and the Salt