What size water filter diverter do you need for your sink? Do you need a male or female diverter? Should you get a diverter that sends water to your water filter, or one that also takes filtered water to your faucet? There is a lot to think about when buying a diverter for your water filter.

Some sinks have a hole with a cover, at the side of the hot and cold water valves, for you to add a soap dispenser or a filtered water faucet. Can you connect a water filter that is expecting you to have a faucet mounted in your sink, to your regular water spout? If your faucet has an aerator at the end then yes you probably can.

If your sink has no place to mount a “filtered water only faucet”, and the faucet has an aerator, you can install a diverter to connect your counter-top water filter.

If your sink has a place to mount a faucet or soap dispenser, the water filter could go under the sink. If your filter will go under your sink, consider the option of installing a valve that pierces into your cold water pipe, to send water to your filter and then connect to the mounted “filtered water only” faucet; this doesn’t use a diverter on your sink’s faucet. (You might want to have a plumber install this piercing valve, so it doesn’t leak.)

If your sink doesn’t have one of these “cut-out” places to mount a faucet, you will have to either drill a hole in your counter to mount a faucet, or use a water filter designed to be on your counter.

An aerator (pronounced “air-ator”) is a small tip on your faucet, that makes the water come out with less splashing, by adding air into the water flow. The tiny air bubbles make the water flow white instead of clear.

You can probably remove the aerator by placing a towel around it (the towel protects the finish so it doesn’t get scratched) and gripping the towel with an adjustable wrench. Looking from above the faucet, turn the wrench from right to left to loosen the aerator.

What Size Aerator Do You Have?

Aerators come in several sizes. Common sizes are the size of a USA quarter dollar coin, a nickel coin, or a penny coin.

There are also different “gender” threads. If the threads are on the inside of your aerator, you need a female diverter. If the threads are on the outside of your aerator, you need a male diverter.

There are adapters available to connect to other size faucets, and for faucets that need the other gender threads.

Faucet Diverters for Water Filters

After finding out what size and gender aerator you have, to know what size diverter you need, you have to pick getting one with a one-way diverter or a two-way diverter.

A one-way diverter sends tap water to your filter; the water filter must have a built-in faucet or connect to a faucet mounted on your sink.

A two-way diverter sends tap water to your filter and also sends filtered water to come out of the diverter. The filtered water comes out right next to where the un-filtered water would.

Both types have a lever or knob, for you to let water out your normal faucet or divert the water to your water filter.

I have not tested these diverters, they just look like they will do the job.

PureSec 2-Way Kitchen Faucet Diverter Valve/Splitter for Counter Water Filter

with Female M22 (≈22mm) Thread

For 1/4″ Outer Diameter Tubing, OR for 3/4″ OD tubing, you select on the order page.

Two way diverter, diverts tap water to your water filter, and then filtered water out of your faucet

Hydicmart Faucet Diverter Valve with Aerator M22 Female Thread, for Faucet Tap to Countertop water Filter

with Female M22 (≈22mm) Thread

Three Styles: Fits Single Way 1/4″ OD Tubing, OR Fits Two Way 1/4″ OD Tubing Outlet, OR Fits Single Way 3/8″ OD Tubing

One-way diverter, diverts tap water to your water filter. You’ll need a faucet wtih your water filter.

Two-way diverter, diverts tap water to your water filter then filtered water out your faucet.

Avalon 2052-1 Faucet Aerator Water Filter Adapter with Diverter 1/8 Inch to 1/4 Inch Barb, Polished Chrome Finish

with Female M22(≈22mm) Thread

1/4 inch barb, fits 1/8 inch to 1/4 inch tubing

2.2 GPM at 60 PSI

One-way diverter, diverts tap water to your water filter. Your water filter needs to have a built-in faucet or connect to a counter-mounted faucet.