Current manufacturer guidance lists G3-N1CF up to 6 months, G3-N3CB up to 12 months and G3P600-RO up to 24 months, with actual life depending on water quality and use.
The three core G3P600 filters
The first-stage cartridge is G3-N1CF, the carbon-block stage is G3-N3CB, and the dedicated 600 GPD membrane is G3P600-RO / WD-G3P600-N2RO.
Replacement schedule
Waterdrop publishes up to 6 months / 550 gallons for G3-N1CF, 12 months / 1,100 gallons for G3-N3CB and 24 months / 2,200 gallons for the RO membrane.
Current list prices
Current one-time pricing is $29.99 for G3-N1CF, $29.99 for G3-N3CB and $109.99 for the G3P600-RO membrane.
Annualized ownership
Using the manufacturer intervals and current list prices, the core cartridge set annualizes to roughly $145 per year before promotions, optional remineralization and tax.
How to verify fit before buying Waterdrop G3P600 Replacement Filters: Schedule, Codes and Annual Cost
Treat compatibility as a model-number decision, not a shape-matching exercise. Start with the appliance or system model label, then confirm the exact cartridge or replacement code listed by the manufacturer. Similar-looking filters can use different tabs, seals, RFID features or bypass interfaces, so a cartridge that appears to fit can still leak, restrict flow or fail to lock correctly.
For aftermarket replacements, separate physical compatibility from filtration performance. A seller can correctly state that a cartridge fits a refrigerator while the contaminant-reduction scope differs from the original filter. If lead, cysts, PFAS or another health-related claim matters, verify the exact replacement model in the current certification or performance documentation rather than assuming an OEM-equivalent claim set.
Compare recurring cost, availability and replacement risk
Replacement products should be evaluated over several service cycles. Multiply the current cartridge price by the realistic replacement frequency, add shipping, and check whether the same model is consistently stocked. A low first-purchase price is less useful if the cartridge becomes difficult to source or if replacement intervals are short.
Watch for vague phrases such as “uses certified media” or “tested to a standard.” Finished-product certification is stronger evidence than a statement about one component. For marketplace listings, clear manufacturer identity, exact model numbers, return policies and traceable certification reduce the risk of counterfeit-style or poorly fitting replacements.