Cigarette burns are so dark and distinctive that it's hard to cover or ignore them, especially if they're reflected in the mirror of a bathroom vanity. Deep burns that leave a crater in the countertop may need to be removed by a professional, although home methods can minimize their appearance. Light, surface burns often can be removed with cleaners and abrasives.
A gentle scouring powder made specifically for countertops or labeled as scratch-free can do double-duty to both bleach and remove the black stain left behind by a cigarette burn. Sprinkle a little powder on the burn and rub in a circular motion with a damp cloth. Add additional scouring powder as necessary, until the black mark is gone. If the stain is on a laminate countertop, there will probably still be a small blister or indentation that cannot be removed. Rinse away the scouring powder with a clean, damp cloth.
For countertops that might be damaged by even the gentlest scouring powder, a little baking soda can provide just enough abrasive action to remove the stain created by the burn without scratching the counter. Use the baking soda in the same way as scouring powder. Scrub the area, using an old toothbrush. Alternatively, use hydrogen peroxide in place of water to increase the scrubbing power.
Light-colored countertops may still show signs of a cigarette burn even after scrubbing with scouring powder. A little bleach may remove the last traces of the stain. Test the bleach on an inconspicuous spot to ensure it won't damage the countertop. Spray or dab the bleach onto the burn, let it sit for a few minutes, then rinse it away. Don't let the bleach remain on the countertop for more than five minutes or it could cause damage.
Sanding and Filling
Sanding is a last resort to removing a burn from the countertop and may cause more damage than the burn itself if done improperly. If you decide to sand and fill the damage, use fine steel wool and sand gently in small circles. Concentrate only on the burn and check your progress frequently. If the countertop is laminate, you can use a seam filler to patch the sanded area. Follow the instructions on the label for applying and smoothing the filler.
Stone or solid-surface countertops may look dull in the area where the burn occurred. This can be fixed by buffing the area with polishing compound. Apply the compound and use a low-speed electric buffer, 2,300 rpm or less, and a thick wool pad to bring back the sheen. Use the buffer gently, taking care not to dig into the surface of the countertop. Your goal is to restore a light sheen over the burned area.