Willem Coymans is an oil painting on canvas by Frans Hals. It is dated 1645. It measures 77 x 64 cm (30 5/16 x 25 3/16 in.) It hangs in the National Gallery of Art, Washington, DC. The Gallery writes, "Hals was the first portraitist who consistently depicted his subjects seated sideways, with their arms hooked casually over the backs of their chairs. Coymans, an elegant dandy proud of his expensive clothes, wears an embroidered jacket and sports a pom–pom on his hat, which is pushed forward rakishly. Hals' dazzling brushwork is especially evident in the gold embroidery and the crisply pleated shirt–sleeve."