Boil Water Notice: What to Do in the UK

A boil water notice is one of the more likely UK water emergencies. It usually follows a burst main, treatment fault, flood contamination or local test result that means tap water may contain organisms that can make people ill. The notice does not always mean the water looks dirty, smells odd or is unsafe for every use, so the safest approach is to follow the official advice exactly until your supplier or local authority says normal use can resume.

What a Boil Water Notice Means

A boil water notice means water from the affected supply should be brought to a rolling boil before it is used for drinking, preparing food, making ice, brushing teeth or making drinks. Boiling is used because it kills the bacteria, viruses and parasites that are the usual concern in this type of incident. It will not remove chemicals, fuel, salt or other pollution, so if official advice says do not use the water at all, boiling is not enough. Always check the exact wording from your water company, council or the UK Health Security Agency advice shared locally.

How to Boil Water Safely

Bring water to a full rolling boil, then let it cool naturally in a clean covered container. In normal UK home conditions, reaching a rolling boil is the important step; you do not need to keep a pan boiling for a long time unless official local advice says otherwise. Use a clean kettle or pan, avoid touching the inside of lids or containers, and store the cooled boiled water away from raw food, pets and household chemicals. Label a jug or bottle if several people are using the kitchen so nobody mistakes untreated tap water for boiled water.

Drinking, Cooking and Brushing Teeth

Use boiled and cooled water for drinking, tea and coffee, squash, brushing teeth, rinsing fruit and salad, and any food that will not be cooked afterwards. You can usually use unboiled tap water for food that will be boiled thoroughly, such as pasta or rice, because the cooking process treats the water, but follow the local notice if it gives stricter instructions. Do not use untreated tap water for ice cubes, water bottles, soda machines or pet drinking bowls while the notice is in force.

Babies, Formula and Vulnerable People

Baby formula needs extra care because powdered formula is not sterile and babies are more vulnerable to stomach infections. Follow NHS formula-making guidance first: use freshly boiled tap water that has cooled for no more than 30 minutes, so it is still at least 70C when it meets the powder, then cool the made-up feed safely before giving it. If you are unsure, if the notice is complicated, or if anyone in the household is immunocompromised, elderly or seriously unwell, contact NHS 111, your midwife, health visitor or GP for situation-specific advice.

Washing, Cleaning and Laundry

You can usually shower, bathe and wash hands with tap water during a boil water notice, but avoid swallowing the water and take extra care with toddlers. Use boiled cooled water for washing open wounds or cleaning contact lenses, and use proper lens solution rather than tap water. Dishwashers are normally acceptable if they have a hot cycle and drying cycle, but hand-washed dishes should be rinsed with boiled water or sanitised if the notice tells you to. Laundry can normally continue unless the local advice says contamination is chemical rather than microbiological.

Filters, Tablets and Bottled Water

A household jug filter does not make water safe during a boil water notice. Outdoor water filters can reduce some organisms and particles, but many do not remove viruses and none should override official advice to boil. Purification tablets may be useful in a grab bag or camping kit, but they need the correct dose, contact time and reasonably clear water. In a UK home, the simplest reliable setup is stored tap water in clean food-grade containers, the ability to boil more, and bottled water as a temporary backup for anyone who cannot safely use boiled water.

What to Keep at Home Before It Happens

Store enough drinking water to avoid panic buying when a notice lands. A practical target is at least three litres per person per day for drinking and basic food preparation, with extra for babies, medical needs and pets. Use clean water carriers or sealed bottles, keep them cool and dark, and rotate them periodically. Add a camping stove or other outdoor-only boiling method for power cuts, plus a head torch so you are not trying to handle hot water in the dark.

When the Notice Is Lifted

Wait for the official all-clear before returning to normal use. Once it is lifted, run cold taps for a short period if your supplier advises it, empty and clean ice trays, replace water in pet bowls, and refresh any bottles filled during the incident. If water is discoloured after the notice ends, report it to your water company and avoid drinking it until you have clear advice. The event is also a useful prompt to refill your emergency water containers while the lesson is fresh.

A Simple Household Plan

Write the water company's emergency number on your household plan, know where your stop tap is, and keep a clean container ready for boiled water. Store a few days of drinking water, keep one method of boiling water that does not rely on the mains, and make sure everyone in the house knows not to use untreated tap water for drinks, teeth or ice until the notice is lifted. That modest setup covers most boil water notices without drama.