While the two are quite similar in terms of ingredients, the biggest difference is in proportions. Fajita seasoning relies more heavily on cumin and tends to be less spicy, whereas seasoning for tacos is typically spicier and relies more on oregano and chili powder. That said, feel free to use this basic taco seasoning recipe as an all-purpose Mexican seasoning for everything from fajitas to chili, then balance it out with an added sprinkle of any extra spices you like!