Yellow is considered to be a warm color within the color spectrum, along with reds and oranges. When you are trying to pair mustard yellow with another color, you should consider your options thoroughly before you make your final choice. Whether you are choosing complementing colors for your wardrobe or walls, adding another color can tie it all together or ruin the aesthetic appeal.
Black pairs well with almost any color. The only set of colors that is not complemented by black are pastel colors. If you are working with bright mustard yellow, black would work well with it. If you are working with lighter mustard yellow, you may want to go with another color.
Violet is a direct complementing color to yellow on the color wheel. Consider the shade of mustard yellow before you pick your violet. A darker shade of yellow goes better with a darker violet.
Chocolate brown pairs well with a lighter, creamy mustard yellow. This rich, earthy tone complements the softness of this shade of yellow.
Fuchsia and magenta are desirable berry color choices if you are working with an earthy tone of mustard yellow. The key to this pairing is to make sure the shade of yellow is the same shade of a berry tone. In other words, use the same level of lightness or darkness of the color.
A shade of purplish-blue pairs well with some shades of mustard yellow. As with other color pairings, it is important to keep the shades of the two colors the same. A darker blue goes better with darker yellow.