A powder room is the one space where you can be a little bold without committing your whole house to it. That is exactly why I love leading with Burnished Rust here. It is a warm, clay-tinged red that feels like terracotta caught in late afternoon light, and in a small windowless room it reads as cozy rather than loud.
To keep the rust from taking over, the rest of the palette stays soft and warm. Warm Oat gives you a gentle backdrop if you do not want rust on every wall, and Soft Cream on the trim and ceiling keeps the edges crisp without going stark white, which would fight the warmth. Think of these two as the quiet friends that let rust do the talking.
Then ground it. Walnut Brown on the vanity ties the wood right into the wall color, and a little Deep Cocoa on the mirror frame or a sconce gives your eye somewhere to rest. Keep that darkest cocoa to the smallest things, a frame or a fixture, so it adds depth without weighing the little room down.