How Often Should You Replace Your Water Filter? A Practical Guide

Water filters don’t come with an expiry date stamped on them, but they do have a working lifespan — and using an exhausted filter is worse than using no filter at all. Here’s a clear guide to replacement intervals for every type of filter system.

Browse our replacement cartridge range to find the right cartridge for your system, or call us on 1800 789 781 if you’re not sure which one you need.

Replacement Intervals by Filter Type

Benchtop & Bottle-Fed Water Cooler Filters (8-Stage KDF)

Replace every 6–12 months depending on water quality and household size. Signs it’s time: returning chlorine taste, reduced flow rate, or visible sediment in the cartridge. See our Benchtop Water Filters Guide and browse 8-stage KDF filters.

Under Sink Water Filters

Replace every 6–12 months as a general rule. Household size matters:

• Single person (low use): up to 15 months
• Couple (average use): 12 months
• Family (high use): 6–9 months

See our Under Sink Water Filters Guide and browse our under sink filter range.

Whole House Water Filters

Sediment pre-filters: every 2–6 months (more frequently if you’re on bore or tank water with high sediment). Carbon filters: every 4–6 months. See our Whole House Water Filters Guide and browse our whole house filter range.

Reverse Osmosis Systems

• Pre and post-carbon filters: every 6–12 months
• RO membrane: every 2–3 years (replace sooner if flow rate drops significantly)
• O-rings: replace with every membrane change

See our Reverse Osmosis Guide and browse our RO range.

Shower Filters

• Single person: every 4–6 months
• Couple: every 3–4 months
• Family: every 2–3 months

See our Shower Filters Guide and browse our shower filter range.

Ceramic Dome Filters (Ultraceram / Doulton)

Replace every 6–12 months. Ceramic domes can be gently scrubbed to extend life, but replace when the dome has thinned noticeably or flow rate drops significantly despite cleaning.

Signs Your Filter Needs Replacing Now

• Chlorine taste or smell returning to the water
• Noticeably reduced flow rate
• Unusual taste, smell, or colour in the water
• Visible sediment or discolouration in the cartridge
• It’s been more than 12 months since the last change

What Happens If You Don’t Replace Your Filter?

An exhausted filter stops removing contaminants — and can actually release trapped contaminants back into the water. You’ll also notice reduced flow, off-taste, and in the case of ceramic filters, potential bacterial growth. It’s not just about water quality — a clogged filter puts strain on your system and shortens its lifespan.

Tips for Staying on Schedule

• Set a calendar reminder on your phone when you install a new cartridge
• Write the installation date on the cartridge with a marker
• Order your replacement cartridge before you need it so you’re never caught without one

Browse our full replacement cartridge range — we stock cartridges for all major filter systems with Australia-wide delivery.

Frequently Asked Questions