You rely on your water system to do one simple job: keep your water clean, clear, and great-tasting. But even the best systems need a little help to keep working their magic—and that help comes in the form of timely filter replacements. If you’ve ever wondered when to replace your water filter, this post is for you.

Like an air filter or oil change, water filters don’t last forever. Over time, they become saturated with everything they’ve removed from your water—sediment, chlorine, minerals, and more. When that happens, your water quality (and system performance) starts to slide.

So how do you know when it’s time to swap yours out? Let’s walk through five clear signs that it’s time for a filter refresh—and how to find the right replacement for your system in just a few clicks.

1. Your Water Tastes or Smells… Off

This is one of the most noticeable (and unpleasant) clues. If your once-crisp water starts tasting metallic, sour, or like your local swimming pool, your filter is likely maxed out.

As filters reach the end of their lifespan, they lose the ability to trap the substances they were designed to remove—like chlorine, sediment, or sulfur compounds. What’s left behind ends up in your glass.

What to Do:

If you’re suddenly reaching for bottled water instead of your tap, it’s time to replace your filter. This is often the first red flag that customers notice, and it’s a simple one to solve.

2. Water Pressure Has Dropped

Low water pressure from your kitchen faucet or under-the-sink system is a classic sign that your filter is clogged. As the filter collects particles over time, water has to work harder to pass through—and eventually, the flow slows down altogether.

This is especially common with reverse osmosis and under-the-sink filtration systems, where sediment buildup can significantly restrict water flow.

What to Do:

Notice a trickle instead of a stream? Don’t assume something’s wrong with your plumbing. It may just be time to replace your water filter. Restoring full pressure can be as simple as popping in a fresh one.

3. It’s Been 6–12 Months Since Your Last Filter Change

Sometimes the answer is straightforward: if it’s been more than 6–12 months since your last change, you’re likely due. Most under-the-sink drinking water filters are designed to last about a year—or less with heavy use.

Summer, in particular, tends to push your system harder. More water consumption (hello, hydration), more cooking, more showers, and more dishes all mean your filters may wear out faster than you think.

What to Do:

If you can’t remember the last time you changed your filter, it’s probably been too long. Mark your calendar for a quick refresh and keep things on track moving forward.

4. You’re Seeing Cloudy or Discolored Water

Clean water should be crystal clear. If you’re seeing cloudiness, floating particles, or any kind of yellow, gray, or brown tint, your filter is overdue.

This is especially important for sediment filters, which remove dirt, rust, and other particles before they reach your tap. When these filters reach their capacity, they can’t do their job—and the results are easy to see.

What to Do:

Don’t ignore visual changes in your water. Even if the taste seems fine, appearance can be a sign that your filter is no longer protecting your system (or your health).

5. You’ve Noticed Build-Up Around Faucets or Appliances

Hard water sneaking back into your home is a subtle (and annoying) sign that your filter may be past its prime—especially if you use a reverse osmosis system alongside a softener. If your filter is no longer removing minerals effectively, you may see scale returning to sinks, showerheads, or even inside your kettle.

This kind of mineral build-up is a clear sign that your water quality is slipping, even if the change has been gradual.

What to Do:

If you’re spotting chalky residue, soap scum, or crusty white rings again, your filter may not be doing its job. Replacing it promptly helps prevent long-term damage to fixtures and restores the water quality you’re used to.

Why Replacing Filters Matters (Even If Everything Seems Fine)

Here’s the thing: even if your water still looks clean and tastes okay, filters don’t last forever. The longer you wait, the more risks you run—like reduced filtration performance, system strain, or even bacterial growth in certain conditions.

Sticking to a regular replacement schedule is one of the easiest ways to:

• Protect your water system

• Maintain high water quality

• Avoid unexpected repairs

• Get the full lifespan out of your system

The good news? Replacing your filter is easy—especially when you don’t have to guess what type you need.

Not Sure Which Filter You Need? We’ve Got You.

We get it—there are a lot of filters out there. If you’re staring at your system wondering where to start, we’ve made it easy.

Take our Find My Filter Quiz, and in under a minute, you’ll be matched with the exact filters for your Dupure system. No hunting, no second guessing—just a quick path to the right replacement.

Final Thoughts: Stay Ahead of Filter Fatigue

Knowing when to replace your water filter doesn’t have to be a mystery. Whether it’s funky taste, weak flow, or just a little overdue maintenance, swapping out your filters on time makes a big difference in how your system performs—and how your water tastes.

If it’s been a while since your last change, now’s the perfect time to refresh. Your system will thank you, your water will taste better, and you’ll avoid bigger headaches down the line.

Ready for a Refresh?

Take the guesswork out of it. Find your filter now →

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