Painting tiles works, mate, but it lives or dies on prep. Tile glaze is the enemy — paint won't grip a shiny, greasy surface, so you've got to give it something to bite into.
Start by degreasing. Bathroom and kitchen tiles carry years of soap scum, limescale and cooking grease, even when they look clean. Hit them with sugar soap, rinse properly, and let them dry fully. Then abrade the glaze with 120–180 grit — you're not sanding it off, just dulling the shine so primer can key. Wipe down with methylated spirit to lift the dust and any last residue.
Now prime. This is the non-negotiable step. Zinsser BIN is your best friend here — it's a shellac-based primer that bonds to glossy, awkward surfaces like nothing else. One thin coat, brushed or rollered, and let it cure. For wet zones you can also use a dedicated tile primer, but BIN is the trade standard for adhesion.
For the topcoat, go with a tough, wipeable finish. In a kitchen splashback or bathroom, Little Greene Intelligent Eggshell or Benjamin Moore Advance (a waterborne alkyd that levels beautifully and hardens up) are both excellent — durable, scrubbable, and they hold up to moisture far better than a standard emulsion. Two thin coats, allowing full drying between, beats one thick gloopy one every time.
Colour-wise, soft off-whites keep a small bathroom feeling clean and airy — Farrow & Ball Pointing or Farrow & Ball Slipper Satin are lovely. Want something with a bit of depth behind a sink? Farrow & Ball Mizzle sits gorgeously in a tiled bathroom.
The big caveat: painted tiles aren't suitable for shower enclosures or anywhere with constant direct water and abrasion. Splashbacks and walls are fine; the wet wall of a shower will fail. And grout lines stay visible — painting won't hide them, so the texture remains.
Give each coat its full cure time before you expose it to steam. Rush it and you'll undo all that prep.