Which cat litter is best for multi-cat households?

Hard-clumping clays earn the most multi-cat recommendations. Dr. Elsey's Ultra is repeatedly cited in r/CatAdvice and r/litterrobot for rock-solid clumps and low dust, while Arm & Hammer's multi-cat lines target heavier use. Reviewers do note you'll burn through clay faster with multiple cats because clumps get large.