Calculator
What do filter cartridges actually cost?
The hidden ongoing cost of a 4-in-1 boiling tap. Most brands need a £45-75 cartridge replacement every 12 months. Over 10 years, that adds up to a serious chunk of the total cost of ownership.
Your filter
Quooker CUBE filter £75. Franke Omni filter £65. Qettle filter £45. Fohen filter £55.
Most brands recommend annual replacement. Heavy households or very hard water may need 2x per year.
Third-party cartridges can save 30-50% but may void warranty on some brands. Check the small print.
Filter cost over time
Over 10 years
£650
Per year
£65
Per month
£5.42
How we calculate it
Cartridge price reflects OEM (original) prices from each brand's UK store at current 2026 levels. We use the standard cartridge, not the upgraded variants.
Replacement frequency defaults to annual because that is the recommended schedule for all 4-in-1 brands. Hard water areas (London, Cambridge, Essex) may need 6-monthly replacement.
Third-party savings can be real but read warranty terms first. Quooker, Franke and Fohen explicitly state that warranty cover lapses if non-OEM filters are used. Qettle is more relaxed.