How Often Should You Replace Your Water Filter Cartridge?

As a rule of thumb, replace a tap-mounted carbon water filter cartridge about every six months. The exact timing depends on how much water you use and your local water quality, but six months keeps the carbon working effectively for most households. Leaving a cartridge in too long means it stops filtering well and can harbour bacteria.

What affects how long a cartridge lasts?

• Water usage: A large household using filtered water for drinking and cooking will use up a cartridge faster.
• Water quality: More sediment or chlorine means the carbon works harder.
• What you filter: Using filtered mode only for drinking and cooking (and unfiltered for washing up) makes a cartridge last longer.

Signs it’s time to change your cartridge

1. The chlorine taste or smell starts coming back.
2. Water flow slows down noticeably.
3. It’s been around six months since the last change.

What happens if you don’t replace it?

An old cartridge stops adsorbing contaminants effectively, so you’re essentially drinking unfiltered water — and a saturated, damp filter can become a breeding ground for bacteria. Replacing on schedule is the single most important thing for clean, great-tasting filtered water.

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Frequently asked questions

Can I clean and reuse a carbon cartridge?
No — once the activated carbon is saturated it can’t be “washed out.” Cartridges are designed to be replaced.

How do I make my cartridge last longer?
Switch to unfiltered mode for dishes and rinsing, and only use filtered water for drinking and cooking.