If you are looking for colors that match royal blue for a painting, for your home or just for fun you have a lot of options. Royal blue, a rich, deep blue that emulates the color of lapis lazuli, has a lot of character and regal association due to its name. Play up its richness and beauty by matching it with similarly luxuriant colors, or let it shine by itself against more neutral hues.
Emerald, garnet and amethyst purple are jewel-tone colors that go well with royal blue because they are equally sumptuous. Blue and green are analogous colors--that is, colors that lie beside each other on the color wheel, and emerald is a good choice for a relaxed, rich match. Garnet, a red-purple, is a good warm color match. Amethyst purple is a lighter color that will play well off the deeper royal blue. For a dynamic contrast to the royal blue, go with an orange, as orange is the complementary color of royal blue.
Metallic colors are largely neutral, but because of their glimmering surfaces they add sumptuousness to the mix. Silver, pewter, gold and bronze all go wonderfully with royal blue and add splendor. Metallic colors can be acquired for either acrylic or oil painting. For house-painting purposes, metallic paints come in a range of colors and finishes, and can be had at better home-decor and -improvement outlets. You can also use metallics to match royal blue if you are planning out the decor for a room.
Shades of Gray
If you want to isolate royal blue and let it shine, use true neutrals such as shades of gray. The gray will not compete with the blue--you have no danger of a color clash and the blue will stand out. Cooler grays, those that lean slightly to the blue, green or violet are better and clearer in combination with royal blue. Warmer grays, like those that lean to yellow or red, can be a bit muddy and should be avoided.