Eufy S1 Pro vs Willow Go

If you’re deciding between the Eufy S1 Pro and the Willow Go, you’re comparing two wearable breast pumps designed for hands-free pumping — but built for very different routines.

Both pumps offer in-bra designs, strong suction, and portable convenience, yet they take very different approaches to comfort, customization, and everyday usability.

In this Eufy S1 Pro vs Willow Go comparison, I break down the real differences in suction strength, flange design, app features, battery life, noise levels, and overall value so you can decide which pump fits your routine best — whether you’re pumping at work, at home, or on the go.

Quick comparison summary:
– Eufy S1 Pro: Best for moms who want app-controlled pumping, built-in heat support, multiple flange sizes included, and extended battery life with a charging case
– Willow Go: Best for moms who prefer a more rigid flange design, simpler pumping modes, and the option to upgrade to a larger collection cup

Prefer to watch? My full video comparison is below. Prefer to read? Keep scrolling for the detailed breakdown.

Editor’s note: Pumping Milk is reader-supported, meaning, at no cost to you, I may earn a commission if you buy after clicking an affiliate link. Learn More.

Is the Eufy S1 Pro better than the Willow Go?

The Eufy S1 Pro and Willow Go both offer hospital-grade suction and hands-free pumping, but they’re designed for different priorities. The Eufy S1 Pro focuses on customization and convenience, with app-controlled pumping modes, built-in heat support, multiple flange sizes included, and extended battery life through a rechargeable charging case. The Willow Go takes a simpler approach, offering strong suction and a rigid flange design with fewer modes and a shorter battery life per charge.

If you want more control, comfort features, and longer portable power, the Eufy S1 Pro is the better option. If you prefer a simpler setup and don’t need app-based customization or heat support, the Willow Go may be enough. The better choice depends on how often you pump, where you pump, and how much flexibility you want during sessions.

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?

This comparison focuses specifically on how the Eufy S1 Pro and Willow Go differ in daily use, rather than ranking the full Eufy or Willow pump lineups.

Photo credit: Pumping Milk

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.

Photo credit: Pumping Milk

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.

Photo credit: Pumping Milk

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.

Photo credit: Pumping Milk

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.

Photo credit: Pumping Milk

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.

Photo credit: Pumping Milk

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.

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.

The Verdict

Choosing between the Eufy S1 Pro and the Willow Go comes down to how much control, comfort, and portability you want built into your pumping routine.

If you want a pump that gives you more flexibility day to day, the Eufy S1 Pro stands out. App-controlled pumping modes, built-in heat support, multiple flange sizes included, and a rechargeable carry case make it easier to customize sessions and stay powered without constant charging. It’s especially well suited for moms who pump frequently or rely on a wearable pump as their primary option.

The Willow Go is a solid alternative if you prefer a firmer flange design or want the option to upgrade to a larger collection cup. However, its shorter battery life, limited app functionality, and fewer built-in features mean it may feel more restrictive for the price — especially for frequent pumpers.

Both pumps can get the job done, but if comfort, customization, and long-term usability matter most, the Eufy S1 Pro is the more versatile choice.

If you think one of these wearable breast pumps could be the right fit for your pumping routine, I’ve linked current purchase options below for convenience.

➡️ Eufy S1 Pro Wearable Breast Pump on Amazon
Best for moms who want app control, built-in heat support, and extended portability with a charging case.

➡️ Willow Go Wearable Breast Pump on Amazon
Best for moms who prefer a rigid flange design and the option of a larger collection cup.

Photo credit: Pumping Milk