Fill the kettle halfway with white vinegar, top it off with water, and hit boil. That is the whole idea. Vinegar dissolves limescale better than any scrub brush, and you do not have to stick your hand in the spout with a toothbrush.

Why the Crust Forms

If your tap water is hard, every boil leaves behind calcium and magnesium deposits. Over a month or two, those deposits build into a chalky crust that makes your tea taste flat and slows your kettle down. A descale every four to six weeks keeps it running like new.

The Ten Minute Descale

1. Mix half vinegar, half water. Fill to the max line so the deposits near the top get covered.
2. Boil the mixture. Let the kettle switch itself off.
3. Leave it sitting for 30 minutes. You will see flakes floating. That is the limescale letting go.
4. Pour it out and rinse the kettle well.
5. Boil plain water once, dump it, boil again. That clears any vinegar taste.

What I Got Wrong the First Time

My first attempt, I skipped the soak and just boiled vinegar then rinsed once. My coffee tasted like a salad dressing for two days. The rinse twice rule is not optional. The second boil is what actually flushes the flavor out of the heating element.

If your kettle is really bad, use full vinegar instead of the half mix and let it sit for an hour. For a plastic kettle, keep the vinegar ratio lower and never let it sit full strength for long.

How Often Is Enough?

Soft water area? Every couple of months. Hard water area, check the spout monthly. If you see white buildup, it is time. A clean kettle boils faster, uses less power, and makes tea that actually tastes like tea.