BumGenius 4.0 Pocket Diaper Review

BumGenius 4.0 Pocket Diaper Review

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The BumGenius 4.0 pocket diaper was the very first diaper I bought for my stash when I was pregnant with The Heir. At the time, I knew very little about cloth diapers, but I had heard good things about the BumGenius brand. Believe it or not, the only one size diapers we bought to use on The Heir were BumGenius 4.0s. Really. All 26 of my original stash of diapers were BumGenius 4.0s. Talk about putting all your eggs in one basket! It could have been a complete failure, and going with one style from only one brand for your entire stash is not something I recommend in general. That being said, I LOVE this diaper. LOVE. I’ve tried a lot of different brands and a lot of different styles, but again and again the BumGenius 4.0 is the diaper I grab most often. What makes it so special? I’m going to tell you!

The Details:

Inner outer

The BumGenius 4.0 pocket diaper is composed of a waterproof PUL (polyurethane laminate) outer and a suede cloth inner. The PUL is what keeps moisture in, and the suede cloth inner forms a pocket inside the PUL shell.  That means that baby will feel less damp and often ends up being more comfortable. Considered a one size diaper, it fits from 8-35+ lbs and accommodates that weight range with 3×3 adjustable rise snaps. The smallest rise fits from 8-16 lbs, the medium rise fits from 17-22 lbs, and the large rise fits from 23-35 lbs. The waist is adjustable with a double snap closure and has stretchy tabs to give a snug fit. The pocket opening is at the back of the diaper with a flap over the opening. At the front of the diaper, there is a strip of PUL on the inside that prevents leaks and wicking at the waist.

BumGenius 4.0 Pocket Diaper Review
3×3 adjustable rise settings.

Two microfibre inserts are included with the BumGenius 4.0 pocket diaper. One newborn sized insert and one adjustable one size insert. The adjustable one size insert has snaps so it can be folded and secured to fit each of the three rise settings. When stuffing the insert in the diaper, you want the adjustable insert folded at the front for a boy and at the back for a girl.

BumGenius 4.0 Pocket Diaper Review
Left: Newborn insert, Right: Adjustable one size insert.

How It Works:

Having used the BumGenius 4.0 pocket diapers on The Heir from about 3 weeks old until 22 months old and using them now on Petit Prince, I have a lot to say about them!

BumGenius 4.0 Pocket Diaper Review
Generous sized pocket and opening.

Something that is really great about this diaper is that the pocket opening and the pocket itself is really roomy. Why does that matter? Well, as baby gets older he tends to become more of a heavy wetter. Having a nice roomy pocket allows you to add more absorbency as needed. Want to use them overnight? No problem! You can stuff the BumGenius 4.0 with thick or multiple inserts without a struggle to get them in the pocket. For the first 10 months with The Heir, I stuffed the diaper with the adjustable and newborn sized microfibre inserts for overnight and it lasted a good 12 hours without leaking. Once he was around 11 months old, he became a heavy wetter and I needed to add a hemp insert with the adjustable microfibre insert to last through the night. The beauty of the BumGenius 4.0 pocket diaper is that there was room for both of those inserts (and more if necessary). It’s also great that the actual pocket opening is generously sized. There’s nothing like trying to force your hand into the pocket opening to get your inserts stuffed. My hands are not large by any means, but even King Dad has no trouble stuffing the BumGenius 4.0 with his man hands.

BumGenius 4.0 Pocket Diaper Review
Flap over the pocket opening.

The flap over the pocket opening at the back of the diaper is a great feature. First, it provides an added layer of suede cloth to make sure the microfibre inserts don’t sit against baby’s skin (microfibre should never be against baby’s bare skin). Another great benefit is that it helps to prevent poopsplosions up the back of the diaper. Though poopsplosions are extremely rare in cloth diapers to begin with, this pocket flap provides another barrier should a newborn poop (or sick toddler poop) be particularly, um, forceful.

BumGenius 4.0 Pocket Diaper Review
Stretchy tabs.

The stretchy tabs at the waist closure are awesome! They allow for a truly snug fit and make a customized fit really easy. If you have a baby with skinny legs but a chubby tummy, you can do up the lower waist snap tighter than the upper waist snap. This tightens up the legs and leaves more room at the waist. If baby has monster thighs and a smaller waist, you can do the upper waist snap tighter than the lower waist snap to accommodate those leg rolls. The stretchy tabs make this really easy to accomplish without resulting in a bunchy closure.

BumGenius 4.0 Pocket Diaper Review
Strip of PUL at the waist.

The strip of PUL on the inside of the waist of the diaper is one of my favourite features. I have never had a BumGenius 4.0 diaper wick or leak up the front at the waist. That strip of PUL on the inside traps moisture inside the pocket shell and keeps it from seeping up.

The suede cloth inner is a stay dry material. I love that! What it means is that baby feels more dry even when the insert(s) inside the pocket are wet. Some babies are particularly sensitive to wetness, but this is a non issue with the stay dry suede cloth inner of the BumGenius 4.0.

BumGenius 4.0 Pocket Diaper Review

What about the fit? It’s pretty great, but not really from 8 lbs. The Heir was over 9 lbs at birth, so it’s hard for me to say if they would have fit him at 8 lbs. They definitely fit him at 10 lbs, which was around 3 weeks old. Petit Prince was fitting well in the BumGenius 4.0 when he was 9 lbs, but they were not fitting great around the legs before then. Consider the recommended weight ranges for each rise setting to be suggestions only. With The Heir, I didn’t move to the medium rise setting until he was at least 18 lbs, and he never moved to the largest rise setting. He was about 24 lbs when he potty trained and was far from needing to move to the large rise setting. So far, Petit Prince has only been on the smallest rise setting, and I don’t see him moving up to the medium rise for quite some time (he’s 15 lbs 5 oz now).

BumGenius 4.0 Pocket Diaper Review

How about absorbency? The “newborn” insert should really just be considered a booster. It was never really absorbent enough on its own, even when the boys were under a month old. It worked well as a booster with the adjustable one size microfibre insert for overnight use, and as a booster when The Heir needed extra absorbency during the day (from about 14 months old). The adjustable microfibre insert has been great on its own for day time use. Petit Prince can go 3-4 hours without leaks. If I’m going to have him in the carrier, I do add a small bamboo insert to prevent compression leaks. Microfibre, though very absorbent, is prone to compression leaks and I find that when baby is positioned in the carrier that a bamboo or hemp insert coupled with the microfibre eliminates that problem.

Needs Improvement:

There is one thing on the BumGenius 4.0 pocket diaper that could use some improvement. It’s the elastics. This is a common concern with BumGenius diapers and if you frequent any cloth diapering Facebook group, you’ll have heard about these elastics. To be fair, I did not find the elastics to be relaxed enough to need replacing before The Heir potty trained. However, many of my original stash of 26 needed their elastics replaced before Petit Prince was born. The good news is that this was fairly simple. If you turn the BumGenius 4.0 inside out, the ends of the elastics are all exposed, so elastic replacement is relatively easy. I did it all by hand myself when I was pregnant. If you know me, you know I can’t sew. By that I mean I don’t even own a sewing machine. I literally did the elastic replacement completely by hand and it wasn’t that hard to do. It was, however, quite time consuming. Even after I figured out what I was doing, it still took me a good 2 hours to replace all three elastics in one diaper (two leg elastics and one back elastic). That being said, it was totally worth doing.

BumGenius 4.0 Pocket Diaper Review
Exposed elastic ends inside the diaper.


  • Stretchy tabs
  • Generous pocket and opening
  • Stay dry inner
  • Strip of PUL inside the waist prevents wicking


  • Weak elastics
  • Newborn insert is not absorbent enough to use alone

Now here’s the bad news… Cotton Babies has discontinued the BumGenius 4.0. I know, right? Here’s the good news! They are on CLEARANCE at most retailers! In Canada, you can snap them up at Bumbini Cloth Diaper Company.

Do you have any BumGenius 4.0 pocket diapers in your stash? What do you think of them?


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8 Comments on “BumGenius 4.0 Pocket Diaper Review

  1. What a thorough review! I’ve never been one to brave cloth diapering, but it seems like such an environmentally savvy choice! Way to go finding a brand that works well for you.

  2. Love your pics! The 4.0 has been a very solid diaper in our stash. I do stuff with different inserts, but I find that BGs fit universally well (though not right away at the lowest weight range) and ours have not had issues with elastics as I have heard others remark!

  3. really need to buy a bumgenius. been wanting the albert print, but now feel like its a must find so i’m not disappointed.

  4. Yay for preventing poopsplosions!!! I cannot believe you did all the elastics by hand!! Way to go mama!

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