The main difference between pressurized vs non-pressurized portafilters is how they create resistance during extraction. A pressurized basket uses a mechanical valve to generate pressure, making it forgiving for beginners using pre-ground coffee. In contrast, a non-pressurized (single wall) basket relies on precise grind size to create resistance, producing authentic crema and superior flavor clarity. Choose pressurized for convenience and non-pressurized for flavor control.

If you have just bought a new espresso machine, you might be wondering about the two types of filters included. Understanding this battle is the first step for any home barista. The portafilter—the handle you lock into the machine—holds a metal filter basket. This basket dictates how you brew, the grinder you need, and the quality of the cup.

For a deeper dive into how these components work together, check out our guide on mastering espresso machines.

What is a Pressurized Basket? (Dual Wall)

A pressurized basket, often called a dual wall basket, is designed to help you get a decent shot of espresso even if your variables aren't perfect. It features a false floor with many holes on the inside, but only one tiny small hole on the outside bottom.

This design creates artificial pressure within the basket. Even if your coffee grounds are too coarse, the basket restricts the water flow mechanically to ensure good extraction. A pressurized basket will tolerate a less precise grind. These baskets typically cost between $15-40, making them an affordable entry point.

A pressurized basket (dual wall) features a false floor that mechanically restricts water flow. This design allows it to generate internal extraction pressure between 8-12 bars regardless of grind size, making it ideal for beginners using pre-ground coffee who want decent crema without dialing in.

Pros of Pressurized Portafilters

• Forgiveness: They allow the use of pre-ground coffee from a grocery store.
• Consistency: You can achieve good results without a high-end grinder.
• Crema: They force aeration, creating a thick foam that simulates crema.

If you own a lower-end machine or use pre-ground coffee, stick to using a pressurized filter. It creates the necessary bars of pressure internally, so you don't have to worry about the physics of the puck.

What is a Non-Pressurized Basket? (Single Wall)

A non-pressurized basket (or single wall) is what professionals use. If you look at the bottom, you will see hundreds of holes. There is no mechanism to pressurize the water for you. Instead, the resistance comes entirely from the coffee puck itself.

To use this type of espresso basket, you need fresh coffee beans and a capable grinder. You must dial in your grind size so it is finely tuned. When you tamp with about 30 lbs of pressure, the water should push through at roughly 9 bars.

Non-pressurized baskets (single wall) rely entirely on the resistance of the coffee puck to build pressure. They require fresh beans ground to roughly 150-250 microns (SCA standards) to achieve a standard 9-bar extraction, rewarding home baristas with richer texture and flavor clarity.

Pros of Non-Pressurized Portafilters

• Flavor Clarity: Without the violent spray of a pressurized nozzle, you taste the true notes of the bean.
• Texture: Produces authentic, oily crema that lingers.
• Control: Allows the home barista to fine-tune the extraction for better tasting shots.

These baskets are unforgiving. If your grind is too coarse, the water gushes through. If it is too fine, it chokes. You need a high-quality burr grinder to make this work.

Key Differences: Pressurized vs Non-Pressurized Baskets

The primary difference lies in resistance generation. Pressurized baskets use a mechanical valve to mask grind inconsistencies, while non-pressurized baskets require precise tamping and grinding to create resistance. Pressurized filters suit convenience, whereas non-pressurized filters offer superior taste potential.

Unlike pressurized baskets, standard baskets offer no resistance other than the coffee puck itself. This means you must dial in your beans with precision. If you aren't sure how to find that sweet spot, read our guide on how to properly grind coffee beans for espresso.

The main difference between pressurized and standard baskets is how pressure is generated. In a non-pressurized portafilter, the grind size and tamping technique create resistance. To prevent edge channeling in these precision baskets, you should use a precision distribution tool to ensure the entire coffee bed is compressed equally. In a pressurized portafilter, the basket itself creates the resistance.

This affects the brewing process significantly. A pressurized basket produces a lighter body and less distinct flavors because the high-velocity extraction can muddle the nuances. While a leveler may not address deep density issues in the puck, using an aesthetic surface leveler can improve workflow cleanliness and provide a perfectly flat bed for the final tamp.

Additionally, the crema differs. Pressurized baskets create large, bubbly foam. Non-pressurized baskets create a dense emulsion of coffee oils. For those seeking to achieve the best flavor, the single wall is superior.

The Grinder Rule: When to Switch

You should only switch to a non-pressurized basket if you own a high-quality burr grinder. Blade grinders cannot produce the consistent particle size needed to prevent channeling. Until you upgrade, the pressurized basket ensures a drinkable cup.

You cannot use a non-pressurized basket with a blade grinder or old preground coffee. The water will flow too fast, resulting in a sour, watery mess. You need a consistent grind to create a solid puck.

To improve consistency, invest in a dedicated espresso grinder. Before investing in expensive puck prep accessories, prioritize a high-quality espresso grinder that produces the uniform particle size necessary for true flavor clarity. Once you have a grinder that can make micro-adjustments, you can swap your pressurised baskets for non-pressurized ones.

The catch with non-pressurized baskets is that a standard blade grinder won't cut it. To get the results you want, you will need a dedicated burr grinder capable of fine adjustments. If you don't have one yet, take a look at our 2025 guide to the best espresso grinders to find one that fits your budget.

If you are still using a basic grinder, the pressurized basket is your best friend. It is designed to tolerate a less precisely ground coffee, ensuring you still get a drinkable cup.

Common Mistakes to Avoid

Avoid using coarse or pre-ground coffee in single-wall baskets to prevent the "sprinkler effect." Additionally, ensure you regularly clean the single exit hole of pressurized portafilters, as dried coffee oils can quickly clog the mechanism and block flow.

• The "Sprinkler" Effect: Using a non-pressurized basket with coarse coffee will spray liquid everywhere.
• Wrong Tamp: You must tamp level and firm. To get the best return on investment for shot quality, we recommend starting your journey with a quality espresso tamper to ensure a firm and comfortable grip for level pressing. In a pressurized filter, tamping matters less.
• Cleaning: The small hole in a pressurized portafilter clogs easily. Clean it often.

For those seeking absolute repeatability, a professional automatic tamper delivers perfectly compressed grounds and a level result with unparalleled precision.

FAQ: Pressurized and Non-Pressurized Baskets

Do pressurized baskets make real espresso?

Technically, pressurized baskets simulate espresso but produce aerated foam rather than true crema. However, for most home espresso drinkers, they provide a convenient and tasty way to brew without needing expensive gear or barista skills.

Can I use pre-ground coffee in a non-pressurized basket?

No, pre-ground coffee is typically too coarse for a non-pressurised basket. The water will pass through the puck too quickly, failing to extract properly. You must use freshly ground coffee dialed in specifically for your machine to use single-wall baskets.

Which basket should a beginner use?

Beginners should start with the pressurised basket because it is forgiving of technique and grind inconsistencies. Once you upgrade your grinder and master the basics, switch to the non-pressurized portafilter to improve flavor and texture.