Paint undertones greatly affect trim and wall pairings by influencing whether colors harmonize or clash visually. Alabaster walls have warm creamy undertones, so trim colors with cold or blue undertones can create an icy, stark effect that conflicts with the walls. Ideally, trim should share or complement the warm undertones to maintain balance. Soft neutrals such as putty or greige work because they reflect similar warmth, enhancing cohesion between walls, trim, and floors. Checking undertones in real light is critical for successful pairing.