Light is the whole point of a coastal kitchen, and large format porcelain across the floor keeps that feeling intact underfoot. Available in wood, stone, cement, or plain finishes, it gives you a calm, low maintenance base in keeping with that breezy, sun-washed feel, without asking for much upkeep in return.
Where coastal style gets to have a bit more fun is on the splashback and surrounds, where a decorative tile in soft blues or sandy tones can bring in real texture behind the hob and sink. In smaller kitchens, that same pattern works beautifully on the floor too, adding personality where a plain surface would otherwise fall flat. Since the kitchen sees more spills than any other room in the house, a tiled surface remains the most sensible protection, whatever finish you choose.