Eufy S1 Pro vs Willow Go

If you’re trying to decide between the Eufy S1 Pro and the Willow Go, you’re in the right place. These two wearable breast pumps both offer hands-free freedom and powerful performance—but they go about it in very different ways.

In this comparison guide, I’ll walk you through everything you need to know about the Eufy S1 Pro vs Willow Go, from suction strength and comfort to battery life, app features, noise level, and more. Whether you’re pumping at work, on the go, or at home with a newborn, I’ll help you figure out which pump fits your routine—and which one is really worth the investment.

Prefer watching? Start with the video below. Prefer reading? Just scroll down for the full written review.

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* Excludes accessories and new releases

Similarities and Differences

The Eufy S1 Pro and Willow Go might look similar at first glance—both are wearable, in-bra pumps designed to give you hands-free flexibility without sacrificing power.

But once you dive into the features, it’s clear these two pumps take very different approaches to wearable pumping.

So what exactly do they have in common? And where do they really start to stand apart?

Let’s take a closer look with my Willow Go vs Eufy S1 Pro comparison!

Pump Design

At a glance, the Eufy S1 Pro and Willow Go both look like modern, in-bra wearable pumps—but once you take a closer look, the differences in their design become more noticeable.

The Eufy S1 Pro has a sleek, tech-inspired look with smooth lines and a soft contoured shape that fits comfortably against the breast. Despite having built-in features like LED controls and heat therapy, the S1 Pro is refreshingly straightforward to put together. The design feels minimal and user-friendly, with just a few components that click easily into place. Each collection cup holds up to 5 ounces of milk, which is ideal for most pumping sessions.

The Willow Go, while it looks a little slimmer on the outside, is actually longer and sits deeper in your bra. Its design is more rigid and involves multiple internal parts that must be aligned precisely for the pump to function well. It uses a one-piece hard silicone flange and a valve system that can be a bit more finicky to clean and reassemble. The standard cup holds 5 ounces as well, but Willow offers a larger 7-ounce cup that can be purchased separately—an advantage if you tend to produce more milk per session.

So while both pumps offer a wearable, all-in-one experience, the Eufy S1 Pro comes out ahead for its clean design, intuitive setup, and fewer pieces to manage—making it easier to use, clean, and reassemble with confidence.

Flange Design

When it comes to flange comfort and flexibility, the Eufy S1 Pro and Willow Go take very different approaches—and those differences can make a big impact on your pumping experience.

The Eufy S1 Pro features a soft, velvety silicone flange that feels gentle against the skin, designed with a 105° angle to better mimic a baby’s natural latch. This angle can help promote better milk flow while reducing pressure on the breast. Eufy also includes multiple flange sizes (17mm, 19mm, 21mm, and 24mm), giving you more flexibility to find the right fit straight out of the box—without needing to purchase inserts separately.

By contrast, the Willow Go uses a firmer, one-piece hard silicone flange available in just two sizes: 24mm and 21mm. While the design works well for many, it doesn’t offer the same soft-touch feel or ergonomic angle as the Eufy. And if you need a different size, you’ll need to buy inserts or replacement flanges separately, which can add time and cost to setup.

So while both pumps get the job done, the Eufy S1 Pro offers a more comfortable, customizable flange experience from the start—making it an easier choice for moms who value fit, feel, and flexibility.

Pumping Modes and Suction Levels

When it comes to pumping performance and app functionality, the Eufy S1 Pro and Willow Go take very different approaches.

Both pumps offer hospital-grade suction — Eufy S1 Pro up to 300mmHg and Willow Go up to 280mmHg — with two basic modes built into the device: stimulation (short, fast pulses to trigger letdown) and expression (longer, slower pulls to draw out milk). But that’s where the similarities end.

The Eufy S1 Pro really stands out when paired with the Eufy Baby app. Within the app, you can access four unique pumping rhythms: Natural, Max, Express, and a customizable Mixed Mode. This gives you greater control over your sessions, especially if you need help triggering multiple letdowns or prefer a gentler expression pattern. While the pump itself only offers 7 suction levels, the variety in rhythm and pacing through the app helps make up for it.

Adding to its edge, the Eufy S1 Pro also includes built-in heat therapy, with 7 adjustable heat levels located at the base of the flange. This warming function helps stimulate milk flow, ease discomfort, and reduce the chance of clogged ducts — all without the need for extra accessories.

The Willow Go also connects to an app, but it’s only available in the US and Canada and has more limited functionality. You can start or pause sessions and view basic stats, but there are no additional modes or in-app rhythm controls. The pump remains fixed to stimulation and expression modes, and switching between them must be done manually. That said, it does offer 15 suction levels, giving you more flexibility when it comes to finding the right suction strength for your body.

So while the Willow Go provides more suction level options, the Eufy S1 Pro delivers more overall control with its app features, heating, and customizable pumping rhythms — making it a more dynamic and adaptable option for everyday use.

And if you’re wondering how the Eufy S1 Pro stacks up against other app operated breast pumps check out my Eufy S1 Pro vs Momcozy M9 review.

LED Screen

Another key difference between the Eufy S1 Pro and Willow Go is the user interface—and the presence (or absence) of an LED screen makes a big impact on usability.

The Eufy S1 Pro includes a sleek built-in LED display that clearly shows your current mode, suction level, and battery status. It lights up in different colors depending on the mode, making it easy to see what setting you’re on at a glance—no need to fumble with your phone during a session.

The Willow Go, in contrast, has no screen at all. To check your suction level or mode, you’ll need to rely entirely on the app, which is only available in the US and Canada. Outside of those regions, the app isn’t accessible, and the lack of visual feedback on the pump can make adjustments a bit of a guessing game.

So while both pumps are app-compatible, the Eufy S1 Pro adds an extra layer of convenience with its simple yet effective LED display—something that makes a big difference during busy or late-night pumping sessions.

Battery Life & Charging

Battery life is one area where the Eufy S1 Pro and Willow Go differ significantly—and it might be a deciding factor depending on how often you pump.

The Eufy S1 Pro offers an impressive battery setup. Once fully charged, the pump can last up to five days of regular use. That’s a big win if you’re a working mom, pumping on the go, or just don’t want to worry about charging every day. The pump charges via USB-C and sits neatly in its included charging case between sessions, so it’s always protected and powered up when you need it.

The Willow Go, on the other hand, provides around 90 minutes of battery life per charge, which translates to roughly three 30-minute sessions. While this might be fine for part-time pumping or occasional use, it does mean you’ll need to charge the pump daily—especially if you’re pumping multiple times a day.

So if extended battery life is important to your routine, the Eufy S1 Pro offers more convenience and peace of mind with its long-lasting charge and streamlined charging setup.

Noise Levels

Both pumps are relatively quiet, but the Eufy S1 Pro runs slightly quieter at around 46dB compared to the Willow Go’s 50dB. In a silent room, you’ll still hear them—but both are discreet enough for most environments.

Price and Value for Money

At first glance, both the Eufy S1 Pro and Willow Go are similarly priced, with retail prices hovering around $350. But when you break down what each pump actually offers for that price, the Eufy S1 Pro clearly delivers more value.

The Willow Go is a solid wearable pump with decent suction strength and dual modes, but it lacks advanced features like app customization, a display screen, or integrated heating. It also doesn’t include smaller flange inserts or offer much in terms of extras unless you purchase them separately—like the 7 oz collection cups.

On the other hand, the Eufy S1 Pro gives you a lot more for roughly the same cost. It comes with multiple flange insert sizes (17mm, 19mm, and 21mm), built-in heat therapy with seven levels, four programmable modes in the app, and an LED display for real-time control—all features the Willow Go doesn’t offer. Even better, with a 16% discount code (PMilkeufy) when buying direct from eufy.com, you can often bring the price down to around $295.

So while both pumps sit in the same price range, the Eufy S1 Pro stands out as the more feature-rich option, offering more comfort, customizability, and long-term value for your investment.

* Excludes accessories and new releases

The Verdict

Both the Eufy S1 Pro and Willow Go are strong contenders in the wearable breast pump space—but when it comes down to features, ease of use, and overall value, the Eufy S1 Pro edges ahead.

If you’re looking for a pump with flexible app-controlled modes, built-in heat therapy, multiple flange sizes included, and a longer battery life, the Eufy S1 Pro delivers on all fronts. It’s quieter, easier to assemble, and offers more control over your pumping sessions—plus the LED screen and extended battery make everyday use feel seamless.

The Willow Go is still a solid pick if you prefer a rigid flange and want the option to upgrade to a larger cup size. But with fewer features, a shorter battery life, and limited app availability (only in the US and Canada), it may feel a bit more limited for the price.

So if you want a pump that combines smart features with comfort and convenience, the Eufy S1 Pro is the better choice—especially when you can get it for less with my Eufy breast pump discount code.