Red is a strong colour with a variety of shades. It can be difficult to pair it with other colours without fear of becoming a fashion "don't." If you're uncertain what works with your red, pick one of the neutral colours for a classic, tailored look every time. White, black, navy and tan are all considered neutral colours.
Bravery is the Soul of Fashion
Mixing and matching colours is what makes fashion fun. Consider inspiration from traditional colour wheel combinations. A monochromatic scheme would combine shades of red and pink within the same outfit. A complementary scheme would combine shades of red and green, while an analogous relationship would combine shades of red and orange. While many of these combinations may sound odd, remember that varying shades of each colour will change the effect. Brown is a shade of orange and looks fantastic paired with a deep red in the fall.
There is no one colour that goes best with red where fashion is concerned. By taking account of the particular shade and the desired effect of the outfit, however, there is certain to be a right choice.