Kendall Charcoal is one of Benjamin Moore's best greys — deep, soft and warm-leaning, which means it behaves very differently from a cold steely charcoal. The trick is to lean into that warmth.
Honestly, the most striking thing you can do is drench the room — walls, woodwork and ceiling all in Kendall Charcoal, with just a sheen shift on the trim (eggshell on the joinery against a matt wall). It reads architectural and cocooning rather than flat. If full drench feels bold, ground the scheme instead.
For that grounding, reach for a warm off-white — a putty or stone tone, never a bright brilliant white, which would snap cold against the charcoal and make it look grubby. Mylands Beehive Place No.140 (LRV 58.6) is a lovely soft option for adjacent walls or ceilings — warm enough to flatter the grey without going yellow. If you do want a true white for ceilings or skirting, Farrow & Ball All White (LRV 92) is about as clean as I'd push it, and even then keep it to the ceiling.
Want more depth? Paint & Paper Library Blue Blood (LRV 16.4) is a gorgeous inky companion — pair it on a feature element like a fireplace or alcove and you get a tonal, dark, tailored scheme. It sits in the same low-light register as Kendall Charcoal so they read as a considered pair rather than a clash.
If you genuinely want a pop, Dulux Fuchsia Falls 2 (LRV 29.8) as a single accent — a chair, a cushion run, a door — gives that warm pink-toned lift that charcoal sets off beautifully.
But my honest steer: do most of your accenting through texture and warm metals — aged brass, bronze, brushed copper, oak, wool. Charcoal this warm rewards material contrast far more than colour contrast.
Keep the whites warm, keep the metals warm, and Kendall Charcoal will sit handsome in any room.