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Coterie vs. Costco Kirkland




Written by:

Barbara Mighdoll

This post is in partnership with Coterie. When you make purchases through links in this post, I may earn a small commission at no extra cost to you. I only endorse products I believe in.

The Diaper Showdown

As a marketing exec and soon-to-be mom of two under two, I’m juggling a thousand things. Worrying about blowouts and diaper rash are not items I care to add to my list. So I decided to put two popular convenient diaper brands to the test to see if the hype of Coterie was worth the trade-off of cheap prices from Costco’s Kirkland. It’s time for the diaper showdown.

TLDR: Kirkland obviously wins on cost, but can’t compete with the premium qualities of Coterie.

Get 10% off your subscription purchase ($76.50 for a month of diapers): EXTRA10

Criteria 1: Absorbency

To test this feature, I poured water on each diaper brand, then felt how dry it was after 30 seconds.


Coterie says its diapers wick moisture away from baby’s skin in less than 16 seconds versus the industry average of 30 seconds. Like magic, this diaper felt incredibly dry despite pouring water on it! And this is a fact: my baby who mostly has been in Coterie his whole life only has had a diaper rash a couple of times and I’d equate that to him staying nice and dry under that diaper of his. 5/5


High absorbency means no leakage, no blowouts, no diaper rash, and a full night’s sleep – the most important aspects of any diaper. Aside from a quick “super absorbent” mention on its packaging, Kirkland does little to prove out its absorbency effectiveness. Upon testing, these seem to perform the same as your average diaper. 3/5


Coterie vs. Costco Kirkland

Criteria 2: Softness


OMG these are so soft! They feel like actual cloth, not crunchy disposable diaper materials. This is the #1 reason we’ve stuck with the brand time and time again – seriously you just need to feel them for yourself.  5/5


To be honest, I expected the Costco brand diaper to feel like straight up plastic. To my surprise these are actually softer than your average drug store brand, but hard to compete against the cashmere-like softness of Coterie. 4/5


Coterie vs. Costco Kirkland

Criteria 3: Safety


  • 0% Chlorine bleaching
  • Fragrance free
  • Lotion free
  • Latex free
  • Rubber free
  • Dye free
  • Alcohol free
  • Free of heavy metal
  • Clinically proven hypoallergenic
  • Dermatologist-tested
  • Paraben free
  • Phthalate free
  • Free of harsh chemicals
  • No VOCs
  • No optical brighteners
  • No animal testing



  • Chlorine free
  • Latex free
  • Fragrance free
  • Lotion free



Criteria 4: Eco-friendly  

Did you know that no diaper is fully compostable, 100% biodegradable or truly eco friendly? Synthetic materials are required for a diaper to function properly.


Coterie diapers are made with wood pulp sourced from sustainably managed forests and has invested a portion of proceeds to accelerate the transition to truly sustainable diapering solutions for all. Coterie also takes part in a Carbon Offsets program, and each time you make a purchase you’ll see in your cart a CO2 Offset added for free. Coterie is thinking about the environment and planning for a sustainable diaper future. 3/5


Kirkland has zero mention of sustainability on its product packaging. These are not built to be eco-friendly and they don’t have any obvious conscious efforts to improve the environment. Very disappointing Costco! 0/5 

Eco-friendly WINNER: COTERIE

Criteria 5: Cost 


198 diapers for $85 on monthly subscription for size 1 (8-12lb baby) = $0.43 each


192 diapers for $39 for size 1 (6-11lb baby) = $0.20 each


Criteria 6: Convenience 


Coterie has three purchasing options: two options allow for direct ordering from the Coterie website, and the newest option allows parents in a bind to pop into their local Whole Foods to grab diapers. Online, you can sign up for a diaper subscription which removes the thinking from ordering diapers monthly – plus you save 10% with the subscription! You’ll automatically receive your diapers just when you need them, and with the convenient text service, you’ll get asked if it's time to size up before your next order arrives. Shipping takes a few days, which is why I’ve docked a point for convenience. 4/5


To buy Kirkland diapers you have two purchasing options: schlep your way and fight the crowds at Costco, or order them as part of your weekly Costco Instacart delivery.  I haven’t been inside a Costco since the pandemic, and you most certainly wouldn’t catch me making an entire trip there just for diapers, however with Instacart you can quickly get same day delivery of your groceries with diapers when you need it. You’ll still need to hit a minimum order to make the delivery fees worth it, which is why I’ve docked a point here as well. 4/5


And The Diaper Showdown Winner is…

While the price of Costco’s Kirkland is much lower than Coterie, the fact that Kirkland’s absorbency falls short means you’ll likely go through way more diapers a day. So that price difference that seemed so attractive, ends up being less significant than initially thought.

Taking this and the rest of the criteria into account, here’s my vote: Coterie is the winner of The Diaper Showdown and definitely worth the hype. Try them for yourself now.

Get 10% off your subscription purchase of Coterie Diapers ($76.50 for a month of diapers): EXTRA10


This post may contain affiliate links including the Amazon Associates Program. When you make purchases through links in this post, I may earn a small commission at no extra cost to you.  I only endorse products I believe in.