MadMax Trade Supply
Prices include the sales tax we pay at purchase (shown for Minnesota; your cart updates it for your ship-to state) and, where noted, shipping. No separate tax line. Order online; we email a secure payment link before anything ships.
Carbon, white and sediment water filter cartridges with a metal housing on a kitchen counter.

Under-Sink, RO & Whole-House Filters

Replacement cartridges and membranes for under-sink, reverse-osmosis, pitcher and whole-house systems, matched by the system model or the cartridge size printed on your current filter. We do not sell water-softener salt. Brand or model names are for compatibility only.

Shop 60 priced items

Price includes shipping and the sales tax we pay at purchase (shown for delivery to Minnesota; your cart updates it for your ship-to state). No separate tax line at checkout. Items marked "Shipping calculated before payment link" have shipping calculated and shown in your payment link before you pay. Typical delivery is a few business days in the contiguous United States. A delivery estimate is confirmed in your payment-link email. Images are representative; tap a picture to enlarge it.

Don't see your exact item? Request a quote for any item below — the form will include the SKU. Request a quote

More items (quote only)

ItemSKU (internal)Price
Under-sink carbon cartridge (by system model)MM-WFC-001Price coming soon — request a quoteRequest a quote
Under-sink sediment cartridge (by system model)MM-WFC-002Price coming soon — request a quoteRequest a quote
Reverse-osmosis replacement membrane (by system model)MM-WFC-003Price coming soon — request a quoteRequest a quote
RO pre-filter set (by system model)MM-WFC-004Price coming soon — request a quoteRequest a quote
Whole-house sediment cartridge (by size)MM-WFC-005Price coming soon — request a quoteRequest a quote
Whole-house carbon cartridge (by size)MM-WFC-006Price coming soon — request a quoteRequest a quote
Pitcher filter cartridge (by pitcher model)MM-WFC-007Price coming soon — request a quoteRequest a quote
Faucet-mount replacement filter (by model)MM-WFC-008Price coming soon — request a quoteRequest a quote

Attributes we list for each item: Filter type, System or pitcher model, Cartridge size, Stage (if a set).

FAQ

How do I find the right cartridge?

Read the model on the filter housing or the part number on the current cartridge. Send that with your quote request if you are unsure.

Do you sell softening salt or resin?

Softener salt is not offered (it ships on pallets). We quote drinking-water and whole-house cartridges and RO membranes. If you need a softener part, send the system model and we will tell you whether we can source it.

How often should cartridges be changed?

Follow your system maker's schedule. Many under-sink carbon filters are changed every 6 months; RO membranes last longer. Water quality and use affect the interval.