Sub-Zero 4204490 Water Filter: Fit, Life & Genuine

Sub-Zero refrigerators are built to last decades, and the 4204490 is the cartridge that keeps their water and ice tasting the way the fridge was designed to deliver them. It is a genuine OEM Sub-Zero water filter — an activated carbon block cartridge that sits inside the fridge, not under the sink — and it is the one part number that covers the Classic, Designer and Pro series. This guide covers the full intent in one place: which Sub-Zero fridges the 4204490 fits, what it actually removes, how long it lasts, how the quarter-turn change works, and the genuine price — from $29.99 with free US shipping on any order amount.

What the Sub-Zero 4204490 Is

The 4204490 is Sub-Zero’s genuine water filter cartridge for its built-in refrigerators. Inside the white housing is an activated carbon block: carbon processed to be full of microscopic pores, giving a small cartridge an enormous internal surface area. As water is pushed through, chlorine and the organic compounds behind tap water’s treated taste and smell are adsorbed onto that surface, and sediment — rust, sand and scale fines — is strained out before it reaches your glass. That is activated carbon filtration doing the job it is built for, and it is the same working principle behind the cartridges in most premium fridges. The 4204490 is certified to NSF/ANSI 42 and NSF/ANSI 53, which means its claims have been tested against those standards for this specific cartridge — certification attaches to the part number, not to a brand name, so the number on the label is the thing to match.

What It Removes — Including Lead

If you searched for water filters that remove lead, this is the short answer for a Sub-Zero owner: the genuine 4204490 is certified to reduce lead, alongside the rest of its list. The product page states the full reduction list, and it is worth reading in full because it goes further than chlorine alone:

Two honest notes on that table. First, “reduces” is the right word: no fridge cartridge removes everything, and a cartridge does not soften hard water or remove dissolved minerals — if your water is hard, that is a different system, not a different cartridge. Second, the list above is the genuine cartridge’s list. A look-alike cartridge shaped to fit the same housing may claim the same reductions without the same certification for that part number, so check the certification against the number you are buying, not against the brand on the box.

Which Sub-Zero Fridges It Fits

One cartridge covers three Sub-Zero series. If your fridge is in any of these families, the 4204490 is the cartridge its manual points to — but treat any fit list as a starting point only, because Sub-Zero has sold a great many model variants, and the final authority is always the same pair of checks: the label on the cartridge you pull out, and your refrigerator’s manual.

The 4204490 is also the correct replacement for the older part numbers 4290510, SUB-4204490 and SUB-4290510 — if the cartridge you remove carries any of those numbers, the 4204490 is the part that replaces it. Read the number off the old cartridge before you throw it away; that number is your order. Never order by fridge model alone, because look-alike models take different cartridges.

How Long It Lasts — 750 Gallons, 12 Months

Sub-Zero’s own performance data sheet for the 4204490 certifies it for up to 750 gallons and up to twelve months, and states plainly: change the disposable filter cartridge every twelve months. That is the figure this guide uses, because it is the manufacturer’s own sheet for this exact part number — the longest-lived fridge water cartridge in our range, and on the same twelve-month rhythm as the air filter in the same fridge. In practice, whichever comes first is the rule: a household that runs the dispenser and ice maker hard may reach 750 gallons before the year is out, and the water will tell you — slower flow, a taste that creeps back, ice that clouds. Write the change date on the cartridge label when you fit it, and the next change takes care of itself.

How to Change It — Quarter Turn, No Tools

The change is a bare-hands job and takes a few minutes. The product page gives the sequence, and it is exactly as simple as it reads:

1. Lift the grille or open the filter compartment — the cartridge sits behind the grille at the top of the fridge on most models; your manual shows the exact spot.
2. Twist the old filter a quarter turn to the left and pull it straight out. A few drops of water are normal.
3. Push the new filter in and twist it a quarter turn to the right until it locks.
4. Flush a few gallons through the dispenser before you drink from it, to clear out any carbon dust, and discard the first batch of ice.

If the flow is slow after a correct change, the usual cause is a cartridge a quarter-turn short of locked — reseat it with a firm twist first. If the filter light stays on after a correct change, our filter light still on after replacing the filter guide walks through the causes in order. And if your water tastes off straight after a change, flush more water through — new carbon sheds dust for the first gallons, and that is normal, not a fault.

4204490 vs 7042798 — Do Not Mix Them Up

A Sub-Zero has two filters, and they do completely different jobs on completely different clocks. The 4204490 is the WATER filter: it cleans the water and ice, and it is changed every 12 months or 750 gallons. The 7042798 is the AIR purification cartridge: it scrubs the air inside the fridge every 20 minutes to keep produce fresh, it never touches the water, and it is also changed every 12 months. They are not interchangeable, they do not fit each other’s housing, and buying one when you need the other is the most common Sub-Zero ordering mistake we see. Our Sub-Zero 7042798 air filter guide covers the air side in full — including the signs it is done and the two-minute swap — and our Electrolux refrigerator water filter guide covers the same water-versus-air question for another premium brand.

Genuine 4204490 Prices

Every order ships free anywhere in the US, on any amount, with processing in 1–2 business days, delivery in 3–5 business days via USPS, and free 30-day returns with a prepaid label. If you are comparing discount refrigerator water filters, the genuine Sub-Zero price is the number to beat — and for a cartridge that lasts a full year, the per-year cost is the honest comparison, not the sticker alone:

Two- and three-packs are priced between those two figures on the product page. At $29.99 for a year of filtered water and ice, the genuine cartridge costs less per month than most households spend on bottled water in a week — and it is the part Sub-Zero tested for that housing. A genuine EveryDrop Filter 1, for comparison, is $39.99 here with the same free US shipping, and our GE SmartWater guide lists the genuine GE prices side by side if your kitchen has a second fridge from another brand.

Genuine Sub-Zero 4204490 Genuine EveryDrop Filter 1

Frequently Asked Questions

How often should I replace the Sub-Zero 4204490? Every 12 months, or at 750 gallons, whichever comes first — that is Sub-Zero’s own figure for this cartridge. Write the change date on the label when you fit it.

Which Sub-Zero models use the 4204490? Classic (BI and CL), Designer (IT, IC, DEC and DET) and Pro (648PRO, PRO3650, PRO4850) series. Confirm against your manual and the label on the cartridge you remove.

Does the 4204490 replace the 4290510? Yes. The 4204490 is the correct replacement for 4290510, SUB-4204490 and SUB-4290510 — if your old cartridge carries any of those numbers, the 4204490 is the part.

Does the 4204490 remove lead? Yes — it is certified to NSF/ANSI 53 and reduces lead, mercury, cysts and asbestos, alongside chlorine taste and smell and sediment under NSF/ANSI 42.

Is the 4204490 the same as the 7042798? No. The 4204490 filters water; the 7042798 purifies the air inside the fridge. Different jobs, different housings, both changed every 12 months.

Do I need tools to change it? No. It installs with a simple quarter turn by hand — twist left to remove, twist right to lock — then flush a few gallons through the dispenser.