Frigidaire ULTRAWF vs WF3CB vs EPTWFU01: What's the Difference?

Frigidaire ULTRAWF, WF3CB, and EPTWFU01 are different refrigerator water filters designed for different filtration systems and models. ULTRAWF is associated with PureSource Ultra, WF3CB with PureSource 3, and EPTWFU01 with PureSource Ultra II. They aren't automatically interchangeable, so check your refrigerator model number or existing filter before purchasing. 

Standing in front of your Frigidaire refrigerator with a flashing filter light is stressful enough. Then you search for a replacement and find three different filter names: ULTRAWF, WF3CB, and EPTWFU01. They all say Frigidaire. They all look similar. So which one do you actually need?

Here is the quick answer: all three are Frigidaire refrigerator water filters, but they are built for different filtration systems and different refrigerator models. They are not interchangeable. The right filter is not the cheapest one or the one with the most certifications. It is the one that matches your specific refrigerator model and existing filter number. This guide breaks down the Frigidaire ULTRAWF vs WF3CB vs EPTWFU01 comparison in plain language so you can order with confidence and stop guessing.

Quick Comparison: ULTRAWF vs WF3CB vs EPTWFU01

Always verify compatibility against your refrigerator model and manufacturer documentation before ordering.

What Is the Frigidaire ULTRAWF Filter?

The Frigidaire ULTRAWF filter is part of the PureSource Ultra filtration system. It is commonly found in select French-door, Gallery, and Professional series Frigidaire refrigerators. The ULTRAWF carries NSF/ANSI 42 and 53 certifications, which cover the reduction of chlorine taste, odor, and certain contaminants like lead and cysts.

The Frigidaire Puresource Ultra Water Filter uses a push-in cartridge design that fits into a specific housing built into compatible refrigerators. The easiest way to identify it is to look at the existing cartridge in your refrigerator. If it says ULTRAWF on the cartridge body, that is the filter you need to replace.

Do not treat ULTRAWF as an automatic replacement for WF3CB or EPTWFU01. The systems are different and the housings are designed for specific cartridges.

What Is the Frigidaire WF3CB Filter?

The Frigidaire WF3CB filter belongs to the PureSource 3 filtration system. It is commonly used in select Frigidaire side-by-side refrigerator models. Like the ULTRAWF, it carries NSF/ANSI 42 and 53 certifications.

The WF3CB is rated for approximately 200 gallons and has a recommended replacement interval of about six months. Its physical design is specific to the PureSource 3 filter housing. Even if another filter looks similar on the outside, the connection points and housing fit can be different enough to cause leaks or improper sealing.

Some refrigerator models may have documented compatibility options between certain filters, but this needs to be confirmed by your exact refrigerator model number. Never assume based on appearance alone.

What Is the Frigidaire EPTWFU01 Filter?

The Frigidaire EPTWFU01 filter is part of the PureSource Ultra II system. This is one of the key differences in the Frigidaire water filter comparison. The EPTWFU01 Puresource Ultra II is found in select newer Frigidaire refrigerator models and comes with NSF/ANSI 42, 53, and 401 certifications.

The additional NSF/ANSI 401 certification covers the reduction of emerging contaminants such as certain pharmaceuticals and other trace compounds. This is a notable difference compared to ULTRAWF and WF3CB.

The EPTWFU01 uses a twist or push installation design that is model-specific. It should not be automatically substituted for the ULTRAWF even though both use the PureSource Ultra name. Ultra and Ultra II are separate systems. Always check your refrigerator model number before ordering.

ULTRAWF vs WF3CB: What's the Difference?

Filtration and Certifications

Both the ULTRAWF and WF3CB carry NSF/ANSI 42 and 53 certifications. NSF/ANSI 42 covers aesthetic effects like chlorine taste and odor reduction. NSF/ANSI 53 covers health-related contaminant reduction such as lead and cysts. Certification alone does not determine refrigerator compatibility. A filter can have the right certifications and still be the wrong fit for your refrigerator.

Physical Design

The ULTRAWF and WF3CB have different cartridge shapes and connection designs. They may look similar in photos but the housing fit is different. Forcing one into the other's slot can result in leaks, poor water pressure, or no water flow at all.

Refrigerator Compatibility

ULTRAWF is commonly associated with French-door and gallery-style Frigidaire models. WF3CB is commonly associated with side-by-side models. But the most reliable way to confirm compatibility is always to check your exact refrigerator model number against the manufacturer's filter recommendation.

Filter Life

Both filters are rated for approximately 200 gallons or about six months of use. However, actual filter life depends on your household's daily water usage and local water quality. Hard water or high-sediment water can shorten filter life.

ULTRAWF vs EPTWFU01: Are They the Same?

No. The ULTRAWF vs EPTWFU01 question comes up often because both include the words "PureSource Ultra." But they are separate filter part numbers for different filtration systems.

ULTRAWF belongs to PureSource Ultra. EPTWFU01 belongs to PureSource Ultra II. These are distinct systems with different filter housings and cartridge designs. The similar naming causes real confusion for Frigidaire refrigerator owners.

If your refrigerator originally used ULTRAWF, do not assume EPTWFU01 fits without verifying through the manufacturer's documentation or your refrigerator's model number. The physical fit may be different enough to cause problems even if the cartridges look similar side by side.

WF3CB vs EPTWFU01: Which One Fits?

The WF3CB vs EPTWFU01 comparison is straightforward: these are two separate filter systems that are not interchangeable. WF3CB serves the PureSource 3 system while EPTWFU01 serves PureSource Ultra II.

Their installation designs are different. WF3CB uses a housing and connection system specific to its refrigerator platform. EPTWFU01 uses a separate twist or push mechanism designed for its compatible models. Forcing a WF3CB into an EPTWFU01 slot or vice versa can damage the filter housing and cause water leaks inside the refrigerator cabinet.

One practical tip: look at your existing filter's part number. That number tells you exactly what to buy. The refrigerator brand alone is not enough information.

Are ULTRAWF, WF3CB, and EPTWFU01 Interchangeable?

No. ULTRAWF, WF3CB, and EPTWFU01 are separate Frigidaire filter models designed for different refrigerator filtration systems. Some model-specific compatibility or replacement relationships may exist, so always verify the exact refrigerator model and manufacturer-approved filter before buying. Never swap these filters based on appearance or price alone.

How to Find Which Frigidaire Water Filter Your Refrigerator Uses

Step 1: Check the Existing Filter

Open the filter compartment and look at the cartridge already installed. The part number is printed directly on the cartridge body. If you see ULTRAWF, WF3CB, EPTWFU01, or another number, that is your starting point.

Step 2: Find Your Refrigerator Model Number

The refrigerator model number is typically located on a label inside the refrigerator door frame, on the side wall of the interior, or behind the kick plate at the bottom of the unit.

Step 3: Check the Owner's Manual

Your owner's manual lists the recommended filter part number for your specific model. If you no longer have the manual, the model number can be used to find documentation on the manufacturer's website.

Step 4: Verify the Replacement Filter

Cross-reference the recommended part number with the filter you plan to purchase. Check the manufacturer's compatibility information to confirm it matches your model before ordering.

Can You Use ULTRAWF Instead of WF3CB?

Compatibility is model-specific. An ULTRAWF cartridge may look like it could fit into a WF3CB housing, but the connection points and sealing mechanism are designed for different systems. An apparent physical fit does not mean the filter will seat correctly or filter water safely.

Some refrigerator models may have documented upgrade or compatibility options between certain PureSource filters, but this must be verified against your exact refrigerator model number. Do not attempt a swap based on guesswork. A filter that does not seal correctly can leak inside the refrigerator cabinet and cause water damage.

Can You Use EPTWFU01 Instead of ULTRAWF?

Not automatically. This is one of the most common mistakes in Frigidaire filter compatibility decisions. EPTWFU01 and ULTRAWF belong to different PureSource systems. Their housings and connection mechanisms are not the same.

Installing an EPTWFU01 in a refrigerator designed for ULTRAWF can result in an improper seal. This can lead to slow water flow, water leaks, or a filter that appears installed but does not actually filter water. Use your refrigerator model number to determine which filter is approved for your specific unit.

Which Frigidaire Filter Has Better Filtration?

This is not a simple best or worst comparison. Each filter meets the certifications required for its platform. Here is what the certification difference means practically:

ULTRAWF and WF3CB both carry NSF/ANSI 42 and 53 certifications. These cover chlorine taste, odor, and certain health contaminants like lead and cysts.

EPTWFU01 additionally carries NSF/ANSI 401 certification. This covers the reduction of certain emerging contaminants including trace pharmaceuticals and other compounds found in some water supplies.

If your refrigerator uses EPTWFU01, the 401 certification is a bonus. But if your refrigerator uses ULTRAWF or WF3CB, the correct filter for that model is still the right choice regardless of the certification difference. Compatibility always comes first. Learn more about NSF certification standards for water filters on Wikipedia.

How Often Should You Replace These Frigidaire Filters?

All three filters share a commonly stated service interval of approximately six months or 200 gallons, whichever comes first. But actual filter life varies. Factors that affect how often you need to replace your filter include:

• Daily water and ice usage in your household

• Local water quality and sediment levels

• Whether the refrigerator dispenser is used frequently

Replace your Frigidaire water filter replacement cartridge sooner if you notice any of these signs:

• Water flow from the dispenser slows noticeably

• Water or ice has an unusual taste

• A musty or chemical odor from the water

• Reduced ice production

• The filter indicator light turns on or flashes

For a deeper guide on timing, check out how often should you replace refrigerator water filter for detailed advice.

How to Replace a Frigidaire Water Filter

Here is a quick overview of the replacement process. Steps may vary slightly by model.

1. Locate the filter compartment. It is usually inside the refrigerator, in the upper right corner, or at the base grille depending on the model.

2. Remove the old cartridge by turning or pulling according to your filter type.

3. Install the correct replacement filter. Make sure it is the approved part number for your refrigerator.

4. Lock or push the cartridge until it seats fully and securely.

5. Run two to three gallons of water through the dispenser to flush the new filter.

6. Reset the filter indicator light if your refrigerator has one.

For a full step-by-step tutorial, visit the how to change frigidaire water filter guide. You can also check how to clean a fridge water filter for maintenance tips between replacements.

Common Mistakes When Choosing a Frigidaire Water Filter

Avoid these mistakes when shopping for a Frigidaire refrigerator filter replacement:

Buying based only on refrigerator brand. Frigidaire makes many different refrigerator lines with different filter systems. Brand alone does not tell you which filter you need.

Assuming all PureSource filters are interchangeable. PureSource Ultra, PureSource 3, and PureSource Ultra II are distinct systems.

Confusing PureSource Ultra with PureSource Ultra II. These are separate products. ULTRAWF is not EPTWFU01.

Ignoring the existing filter number. The part number on your current cartridge is the fastest and most reliable way to find the right replacement.

Choosing based only on price. A cheaper filter that does not fit your refrigerator is not a deal. It is a problem.

Forcing a filter that does not seat correctly. If the cartridge does not click or lock into position easily, it may be the wrong part. Do not force it.

Forgetting to check the refrigerator model number. The model number is your most accurate compatibility reference.

Confusing refrigerator water filters with PureAir air filters. These are completely different products. Frigidaire PureAir filters handle air quality inside the refrigerator. Water filters handle water and ice filtration.

After replacing your old filter, consider learning about how to recycle refrigerator water filters to dispose of it responsibly.

Frequently Asked Questions

Is ULTRAWF the same as WF3CB?

No. ULTRAWF belongs to the PureSource Ultra system and WF3CB belongs to the PureSource 3 system. They are designed for different refrigerator models and are not interchangeable.

Is EPTWFU01 the same as ULTRAWF?

No. EPTWFU01 is part of PureSource Ultra II while ULTRAWF is part of PureSource Ultra. They are separate filter systems with different housings and certifications.

Can I use WF3CB instead of ULTRAWF?

Not without verifying through your refrigerator model number and manufacturer documentation. Physical similarity does not confirm compatibility.

Can I use ULTRAWF instead of EPTWFU01?

No, not automatically. These are separate filter systems. Using the wrong filter can result in leaks or improper filtration.

Which Frigidaire water filter should I buy?

Buy the filter that matches your refrigerator model's recommended part number. Check the existing cartridge or the owner's manual to confirm.

How do I know which Frigidaire filter fits my refrigerator?

Check the part number printed on your current filter cartridge. Then confirm using your refrigerator model number and the manufacturer's filter compatibility information.

How long does a Frigidaire ULTRAWF filter last?

The ULTRAWF is rated for approximately 200 gallons or about six months, whichever comes first.

How long does a WF3CB filter last?

The WF3CB is also rated for approximately 200 gallons or about six months.

How long does an EPTWFU01 filter last?

The EPTWFU01 is rated for approximately 200 gallons or about six months as well.

What is the difference between PureSource Ultra and Ultra II?

PureSource Ultra uses the ULTRAWF cartridge while PureSource Ultra II uses the EPTWFU01 cartridge. They are separate filter systems for different refrigerator models. Ultra II adds NSF/ANSI 401 certification for emerging contaminant reduction.

Do ULTRAWF, WF3CB, and EPTWFU01 use the same filtration technology?

They all use activated carbon-based filtration but are certified to different NSF/ANSI standards. EPTWFU01 adds NSF/ANSI 401 coverage that ULTRAWF and WF3CB do not include.

Final Verdict: Which Frigidaire Filter Should You Choose?

The answer is simpler than it looks. Use this decision guide:

• Your refrigerator calls for ULTRAWF: Buy the Frigidaire Puresource Ultra Water Filter ULTRAWF.

• Your refrigerator calls for WF3CB: Buy WF3CB. Do not substitute.

• Your refrigerator calls for EPTWFU01: Buy the EPTWFU01 Puresource Ultra II cartridge.

• Not sure: Check the existing cartridge for its part number. Then confirm using your refrigerator model number before ordering.

The correct filter is the one built for your refrigerator. Not the one with the most certifications. Not the lowest-priced option. The one that fits and functions the way your refrigerator was designed to use.

Final Thoughts

Choosing between Frigidaire ULTRAWF vs WF3CB vs EPTWFU01 is not about picking the most impressive option. It is about matching the right cartridge to the right refrigerator system. All three filters serve the same purpose but they work in different systems and are not interchangeable without verifying your model.

When it is time to replace your Frigidaire water filter, start with the part number on your current cartridge. Confirm it against your refrigerator model. Then order the correct replacement. That simple process protects your refrigerator and keeps your water quality consistent.

Find the Right Frigidaire Filter at Frost Water Filter

At Frost Water Filter, we make it easy to find the right Frigidaire replacement filter without the guesswork. Whether you need ULTRAWF, WF3CB, EPTWFU01, or another compatible part, our product listings include compatibility details so you can order with confidence.

Browse Frost Water Filter today and replace your filter the right way. Clean water starts with the right cartridge.