UPDATED!! Wearable Breast Pump Comparison for all my Elastigirls: Elvie vs Momcozy vs Willow Go

If this post contains any links they may be affiliate links for which I may receive a commission if you click on the link and purchase the item. All opinions remain my own.

“The future is now.” At least that’s what I thought when I bought my Elvie pumps a couple weeks after Rigel was born. I was pretty convinced that these pumps would have milk overflowing my house. The reality was a bit more complicated. I have learned a lot since my first breastfeeding journey. While wearable pumps should not be the only pump you rely on, I still firmly believe that they have a place in your breast pump stable if you’re an exclusive pumper. This time armed with lots of knowledge I have endeavored to try all the breast pumps so that maybe you don’t have to.

Before I get into the comparisons let’s talk definitions. A ‘wearable breast pump’ is a pump that is worn completely within the bra and has no external tubing, the motor for the pump is attached to the collection cup. There are now lots of companies making wearable breast pumps but the ones I’m going to discuss are the ones I own, the Elvie, Momcozy S12, and Willow Go.

Elvie (The OG)

The breast pump that started it all, hailing from London, England, Elvie actually started its venture into women’s postpartum health with the release of their pelvic floor trainer. The Original Elvie was the first wearable breast pump I ever bought back in 2019, a couple weeks after my son was born. I was not only excited to try out some new technology but I hoped that it would make getting breastmilk for my son who was not super interested in the anatomy of my nipples, easier. At the time of it’s release I don’t think anyone really knew the issues with wearable breast pumps, like they don’t tend to drain the breasts as well as a traditional flange does for most women, so I had no idea that I should be limiting my usage of them to about a third of the times that I pump.

Elvie Pump with the Legendairy Milk Hack.

Now let’s talk about the pump! The Elvie has the slimmest and sleekest profile of the three wearable breast pumps that I own. Its suction was designed to mimic the way it feels when a baby nurses. For this reason, the suction on the Elvie is the most gentle of the three wearables that I have. For some this suction pattern can be occasionally a bit triggering and for others it’s just ineffective. I have found with time that I have gotten used to it.

Wearing the Elvie Pump.

Now thanks to that slim profile that I mentioned earlier Elvies are notoriously bad for women with elastic nipples due to the short length of the flange tunnel. With my son, my supply wasn’t very big so it wasn’t a big deal to not get too close to empty but not emptying as often probably contributed to my low supply. This time around with a much larger supply, leaving too much milk behind can be disastrous and result in gnarly and painful clogs, so I set out to find a way to make this very expensive ($549 for the pair) pump work more effectively for someone that’s an elastigirl like me. In my search, I stumbled on the Legendary Milk flange hack. This hack requires that you insert a Legendary milk silicone flange, once inserted you can put in a flange insert to get your correct size. This hack effectively elongates the flange tunnel so that your nipple doesn’t block the suction holes and limit the suction power.

Elvie with the 24mm Legendairy Milk Silicone Breast Shield and 21mm Maymom insert.

I tried this hack and my output with the Elvies doubled and now I get at least 80-90% of my usual output consistently (at least 4oz per session). For me doing this hack adds 2 additional parts to clean and assemble. Assembling it requires even more precision now because you have to make sure that this silicone flange does not cover up the suction holes and this flange isn’t exactly designed for this use. But it does work.

Output with Legendairy Milk hack on Elvie after about a 25 minute pump session.

The big reason why I am desperate to make these pumps work besides the cost of the pump is the fact that the pumps can be controlled through an app. The ability to control the pumps through an app adds discretion when pumping in public because you’re not shoving your hands down your shirt every few minutes like you have to with the Momcozy pumps or the Willow Go. The other thing that makes them desirable for when you’re out of the house and need to pump in public is the fact that they are so quiet, they are still the quietest pumps on the market. I have pumped while at the movies, at the doctor’s office, and at many restaurants without being a nuisance or weirding anyone out. I also really like the fact that the pumps are so light. Of the three wearable pumps that I own, they are the lightest. Their lightweight means that they don’t tend to weigh down my bras or my breasts too much as the containers fill up with milk. Not to mention the containers are sealable for easy storage in a pinch which means no pouring anything out in a dark theater.

The only reason why I may not pack them in my diaper bag more often or use them around the house is that they really are not the most effective of the current wearable pumps. That being stated I find them the easiest to clean while on the go. I just wish Elvie would design a breast shield for women with elastic nipples to once and for all solve this problem correctly and give us the quiet pump we deserve.

Momcozy S12

Momcozy used to be a kind of sketchy-looking breast pump company on social media but in the last couple of years they have become a bonafide purveyor of affordable breast pumps and breast pumping accessories. The Momcozy S12 was brought up to me by a couple of followers and being the gadget geek that I am I could not say no to giving this one a try. At the regular price of $139 (though it goes on sale a lot on Amazon) it was worth a pump.

Momcozy S12

Well, that affordable pump is something kind of special because despite the low price it most consistently gets the best output out of all the wearable pumps I own, between 90-95%. Now I will say I don’t love the pour-out cups – they make me nervous and the plastic used for the cups can feel a little cheap but I’m getting used to it. I also wish the motor didn’t come up out of the shirt so much but hey the design works so I can’t be that mad at it.

Momcozy S12 front and side view.

The pumps do not sync up with each other so depending on how synchronized your hands can be when turning them on or switching modes you might get a bit of a cow being milked, alternating pump experience. Some people find that triggering, I have gotten used to it though I still try to start them as close together as possible. The pumps also do not connect to an app so you have to stick your hands in your shirt to switch between modes or intensities. That makes pumping in public a bit more obvious than the experience you might have with the Elvie pumps.

While they are not as quiet as the Elvie, I don’t find them too offensive and have used them at restaurants and at museums. The most difficult thing about them is the fact you have to transfer the milk and can’t transport the milk back home in the container it got pumped in to. This means needing to find a spot to pour out. At the museum, I found a bench and took a few minutes to pour into a bottle I had packed. However, the silicone breast shield on the cups is incredibly comfortable and forgiving for someone with elastic nipples and it makes the flange tunnel long enough to accommodate pretty much all nipple lengths. The other great thing about the cups is that they happen to be available through a lot of different companies, as they have become the cup of choice for most of the budget wearable pumps. For example, my Idaho Jones Pump-A-Collect cups are identical to my Momcozy cups, meaning I could carry around one set of cups and use them with my Momcozy motors or with tubing if I needed extra power or a quieter experience (in the case of hooking them up to my Elvie Stride pump).

Momcozy S12 cups after pumping.

The suction on these motors is also pretty powerful, I would say that the suction pattern is most similar to the Baby Buddha but at a slightly lower intensity. If you can tolerate or enjoy the Baby Buddha experience you’ll probably like this wearable pump a lot. However, due to this suction pattern, some women find it a bit too aggressive. That being stated, I highly recommend this pump if you’re on a budget and looking for something that just WORKS.


Since writing this comparison and my supply regulating I don’t enjoy the suction on these motors as much anymore. I find it to be a bit too aggressive and sometimes it really bothers me to the point that it inhibits letdowns. So I have been using the cups that come with the S12 and using suction caps to connect them to my Pumpables Genie Advanced instead.

Willow Go

The last wearable breast pump that I’ve purchased and the one that I had the highest hopes for is the Willow Go. A lot of people are really jazzed about the Willow Go. With only four parts to it, women were excited at the prospect of having fewer parts to clean. Also due to the length of the flange tunnel elastigirls thought this would be a quality wearable pump that they could finally maximize their output with. I also decided to take the risk and purchase this pump on BemyBreastfriend’s recommendation, since she really likes it. Well, I like this pump the least of the three.

Willow Go Pumps

Allow me to explain. This breast pump feels superior in it’s build quality to the Momcozy but when you look at the mechanics of how it works it’s pretty much the same, except the suction pattern is similar to a Spectra and the pump itself is much heavier than a Momcozy. The pump uses an app but the app can’t change any of the settings; it only tells you what the settings are and how long you’ve been pumping for. It doesn’t even keep a log of your pump sessions! So you have to dig around in your bra and push the buttons to switch between settings and modes. I found the buttons harder to push than on the Momcozy. Meanwhile, it’s about $200 more expensive than the Momcozy. That’s right, you’re paying for Momcozy level tech at almost Willow 3.0 prices. I suppose they still could at some point do a firmware update and let you control the pumps via the app but at this point there appear to be no plans to do so.

While the flange tunnel is in fact longer, I find that I have a hard time maintaining my alignment due to the weight of the pumps unless I am wearing a very supportive bra (which has been hard to do in this early postpartum period when constriction isn’t advised). For reference, the Elvie pumps weigh about 7oz each (before pumping) and the Willow Go pumps weigh about 13.5oz each. This extra weight means that the pumps have a tendency to want to slide and drag my boob with them. Now there are women who say that there is an adjustment period with the Willow Go and eventually you start to ignore the weight difference but for me, it’s been hard to feel like using them more often because my output is so much lower with them than it is with the other two wearables; about 75% of what my usual output is.

Output on Willow Go after doing an extended session.

The pumps are also a pour-out cup design like the Momcozy, so they can be a little tricky to pour due to the weight of the device. I thankfully have never had a spill but some women have reported having them when the container is near full. I also find that due to their design, they are much harder to clean on the go when you don’t have access to a sink than the Elvies. And you have to find a spot to sit to pour out. They are not as quiet as the Elvie pumps but about the same noise level as the Momcozy. I would probably never take these into a theater-type experience or any other place that required me to keep my noise level low.

Wearing the Willow Go front view and side view.

While your nipples will probably not be harmed with this pump since it does have the longest flange length of the three pumps I would not recommend it if you find that you struggle with alignment. If you’re like me and also have a nipple that is flat you might have a hard time finding the right spot with the Willow Go and even when you do find the right spot it might easily slide off. And in quantity testing done by Karing for Postpartum, she found that when she used the Willow Go that she was leaving behind 3oz of breastmilk! My own experience has been very similar to hers and I have had to do multiple sessions in order to get close to 90% empty. I recommend you read her post as you do your own research into wearables as it helped me a lot in pulling the trigger with buying the Momcozy.


A few weeks after I wrote this review Willow updated the firmware on the Willow Go and updated the app, so that you can control the suction strength through the app. Since making this change my love for the Willow Go has actually grown. I respond so much better to it now and it is the pump I reach for now when I want to go tubeless. What a change a little bit of code can make. I would say if you purchase this pump give yourself at least two weeks of regular use for your body to get use to it. I still find them to be heavy which makes it difficult to do stuff with but it’s my favorite museum day pump now.

Final Thoughts

As an almost exclusively pumping breastfeeding Mama, in order to maintain any kind of life balance it’s pretty necessary to be able to pump on the go. No single pump will work for everyone in every situation. I have found that having options this time around is what has made my breastfeeding journey so successful. I would say if you’re in the market for a wearable start with the Momcozy, it’s the most reliable option and the least expensive, giving you the most bang for your buck. If you know you need low noise and a low profile then go with the Elvie but know it’s probably going to take tinkering to find your perfect setup with it and that you should limit your sessions with it to no more than two per day if you find that it’s not draining you enough. The Willow Go is a no go in my opinion. I know some Mamas really like it but I just can’t recommend it due to the high possibility of it not working out for you.

You do not need to be one of those Mamas that does not leave the house until baby starts solids or doesn’t do date nights. With a little planning and a reliable wearable you can keep enjoying yourself while still providing that liquid gold to baby.

Let me know in the comments if you’ve tried a wearable pump and what your experience was. Also let me know what your strategies are for pumping on the go and whether you’ve limited what you do since you started breastfeeding.


I would still suggest that you start with the Momcozy S12 or either of the Pros before spending more money but I will say that the Willow Go is an elegant option, especially if you have to change your settings often during your pumping session but don’t want to be digging around your chest in public. It’s become a great pump to use since they tweaked the software and I will definitely be keeping around for next baby.

Remember to Pump it Up,

Author: Grace G.

New Mom and Retired Lawyer trying to share the ride.

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.