When drilling through tile, it is important to use a specialized drill bit that can penetrate the hard surface without cracking or damaging the tile. The best drill bit to use for bathroom ceramic tile is a carbide-tipped masonry bit, which can cut through the fire-hardened glaze. Diamond-tipped bits are also a good option, especially for drilling through harder materials like porcelain and glass tiles. While diamond-tipped bits are more expensive, they can drill through any type of tile and are more durable than carbide bits. It is important to note that regular twist-drill bits or masonry bits are not suitable for drilling through tile. When purchasing a drill bit, it is important to consider the type of tile being drilled and choose a bit that is appropriate for that material. Carbide-tipped drill bits are also suitable for drilling through concrete and masonry.