A perfectly balanced neutral color palette may come across as effortless, but any designer will tell you that getting neutrals 'just right' is an art form. The reason? Neutrals aren’t really neutral at all. Each one carries subtle undertones that can either harmonize beautifully or clash in a way that leaves a space feeling flat, mismatched, or even unintentionally cold.
"The biggest challenge I see when speaking to clients is that people often think neutrals are the 'safe' choice, but they can actually be quite tricky," says Tash Bradley, director of design at paint company Lick. The secret to a rich and layered neutral space lies entirely in paying attention to the undertones — a concept I'm dubbing the 'hidden hue rule'. Just like with bold, saturated, or bright color palettes, matching the hidden undertones will ultimately lead to a more curated space.
Perfecting a neutral color scheme isn’t about stripping color away. It’s about honoring the beauty of undertones. Once you train your eye to see them, your rooms will never look the same. Here's everything you need to know.
What Is the Hidden Hue Rule? And Why We Care About Undertones
The hidden hue rule highlights the significance of undertones in color theory in a way that makes it easier to understand when creating a color palette.
Simply put, undertones are what make or break a neutral palette, and matching undertones matters because it creates flow. Interior designer, Nina Lichtenstein, explains it by saying, "Think of it like tuning instruments in an orchestra: when they’re in harmony, you don’t notice each note, you just feel the music. Rooms designed with aligned undertones achieve that same effect."
The biggest roadblocks in decorating with neutrals often stem from assuming that all neutrals play well together. "A creamy beige might look lovely on its own, but pair it with a cool gray and suddenly the warmth in the beige reads yellow, even dingy. The same happens when combining whites: one with a hint of pink can make another with a green cast look sickly," says Nina.
Without recognizing the undertones, what should be serene quickly feels out of balance. It’s this subtle discipline that separates a neutral scheme that feels intentional from one that feels unfinished.
How to Use the Hidden Hue Rule in Your Home
So how do you choose neutral paint colors that belong together? Start the way you would with any color palette: by choosing an anchor color and identifying the base undertone. Neutrals always lean one way or another, toward blue, green, pink, violet, yellow, or orange. The key is to stay consistent.
From there, look for complementary shades on the color wheel that share a similar undertone, whether that’s warm, cool, or even slightly pink or green.
For example, Nina explains, "If your anchor shade is a cool gray with a blue undertone, look for complementary cool-based taupes, whites, or charcoals to support it. If your foundation is a warm greige, pair it with neutrals carrying similar warmth so they reinforce one another rather than compete."
Tash Bradley adds that the undertones need to complement the light direction of your room. "Warmer colors, like White 06 or Taupe 03, will work well as a paint color for North-facing rooms or East-facing rooms, whereas cooler undertoned colors, like White 04 or Grey 01, would feel cold in these spaces," says Tash.
When it comes to decor, try rounding out your neutral palette with coordinating throws, rugs, upholstery, and decor. "This will help you create the mood you want in a space — whether light and refreshing or cozy and warm," says Nina.
"Mixing within the same undertone family creates cohesion, while adding texture through fabrics and finishes keeps the palette interesting," says Tash. When neutrals are in harmony, they allow the other elements of the room, like furniture and artwork, to shine without ever looking bland.
Neutral Palettes That Use the Hidden Hue Rule
Warm harmony
Cool Serenity
Modern Greige
Earthy Neutrals
When done right, undertone-matched neutrals don’t just blend, they elevate. Everything feels intentional and soothing to the eye, creating flow in a space rather than disruption.
"This is when neutrals stop being a backdrop and become the design itself," says Nina. The depth and richness created rival most vibrant color palettes.
