White 03 from Lick is a warm white, and that's the key to getting it right. It's got a soft yellow undertone that makes it work beautifully as a whole-room envelope alongside warm woods, linen and aged brass. But that same undertone is also the trap: stick a cool grey next to it and the yellow reads sallow, almost dirty. So your job is to lean into the warmth, not fight it.
For woodwork and trim, Paint & Paper Library's Slate IV (LRV 67.5) is a lovely match — it's gentle enough to sit quietly against White 03 without throwing a hard contrast, keeping the whole scheme soft and considered.
When you want a bit more depth on a feature wall or in joinery, reach for a chalky green. Mylands Artichoke BH.13 (LRV 27.6) is exactly the muted, slightly dusty green that flatters this white — it has enough earth in it to harmonise with the warm undertone rather than clash. It's a cracking pairing for a snug or a study.
For a genuine anchor — think a deep, moody accent on a single wall, a fireplace or cabinetry — Dulux Sapphire Springs 1 (LRV 6.4) brings real drama. At that low LRV it reads almost charcoal-blue, and the contrast against White 03 is striking without going cold, provided you balance it with plenty of those warm textures.
The 'but what about greys' question: I know cool greys feel like the safe, modern choice, but with White 03 they're a mistake. If you want a neutral partner, go for something with a warm or greenish bias rather than a blue-grey. Trust me on this one — the yellow undertone is unforgiving.
Practical advice: always test White 03 with your chosen partners on the actual walls, on big A2 boards, and look at them at different times of day. North-facing rooms will pull that warmth slightly cooler, so the warm pairings matter even more there. Dusty pinks and muted clay tones are also fair game if green's not your thing — same warm logic applies.