
A big part of why I launched the Underwear Thesis is to find underwear that’s well-made, but also affordable. So when lots of people recommended I check out Felina underwear, I knew it would be a great opportunity. If you’re unfamiliar, Felina is sold at Costco as well as directly from the brand. For the purposes of my highly scientific research, I chose to focus solely on the two styles I found at Costco. Let’s begin!
If you’re new to my Underwear Thesis, I encourage you to read these posts before proceeding:

My Search for The Most Comfortable Underwear
This post is an excellent starting point and lists out ALL of the criteria of this project, including:
- Judging criteria
- Commonly used terms
- My size + body type details
- and a lottt more

What to Look for When Shopping for Underwear
Including:
- Fabric and trim
- Seams and stitching
- Gusset
- Size and fit
- Washability

How to Wash Underwear So It Lasts Longer
Including:
- Delicates bag
- Cold water + gentle cycle
- Detergent
- Fabric softener
- And more!

My Totally Unfiltered Review of Felina Underwear from Costco
Please keep in mind that these are my personal opinions of the product. If you love Felina underwear, that’s great! I applaud you! But if you’re on the fence about whether to buy them or not, this is what I think you need to know in order to be an informed consumer.
Styles Tried and Price
- Felina Ladies’ Organic Cotton Stretch Bikini, 6-pack, size large – $14.99
- Felina Ladies’ Cotton Stretch Hipster, 5-pack, size medium – $14.99
I opted for large in the bikini because there were no mediums for sale at my Costco store.
Fabric Quality + Details
Grade: B+
Given the price of the underwear, the fabric is pretty nice! It’s soft like a t-shirt and not too bulky. Just a really good basic cotton! Both cuts had a good amount of stretch and then bounce back to shape. The bikini style has a thin elastic at the waist and leg openings that’s reasonably soft and doesn’t dig in. It actually digs in less than the Auden elastic. If you’re looking for the most stretchiness, I recommend the bikini.
As for the hipster style, there is no exposed elastic trim. Instead, the waist band is made of the same fabric that seems to be bonded to itself and then stitched down. It’s really wide, which I don’t love because it definitely cuts in, creating muffin tops. As for the leg openings, there’s a thin elastic that’s similar to that used on the bikini style.


Manufacturing Quality
Grade: B-
Each pair of Felina is made well enough considering that they are essentially a fast fashion item. There are loose threads and some areas of loose stitching. But in my mind, that is to be expected given the price and brand.
Ethical Practices and Sustainability
Grade: D
I mean… there is literally ZERO mention of Felina’s manufacturing processes aside from “Made in Thailand” which is synonymous with ‘sweatshop’ in my mind, to be perfectly frank.
In terms of sustainability, I think Felina puts a lot of stock in using 91% organic cotton and plant-based dyes and assumes that’s enough. But let’s be real: that’s just green washing. If you care in the slightest about the environmental impact of the underwear you buy, this isn’t the brand for you.

Inclusivity
Grade: D
Felina strikes out again! Not only does the product photography show zero diversity in skin tone, the size range offered is Small through XL for the organic cotton briefs and XS – XXL for the hipsters. It’s 2022, we need to expect more from these brands!
Washability
Grade: D
For the first few months, my Felina underwear washed very well. And then I pulled out a mangled pair from the washer… what on earth happened?! Mind you, they have not gone through a single dryer cycle and were always air dried! So far this has only happened with one pair. But is it a matter of time until the others are ruined, too?


Fit & Comfort
Grade: B+
Honestly, both pairs of Felina underwear are pretty darn comfortable. They are great basic, boring cotton underwear that does it’s job with zero frills. The coverage is exactly what I want and the seams don’t dig in. I don’t love the wide band on the hipster style because it does cut in, but that could be because they are a size medium instead of large.
I give them a B+ because the gusset seems to be sewn sort of far back. I would prefer it to be further forward.

Overall thoughts
Grade: C
I really struggled to assign an overall letter grade to these Felina underwear styles. On one hand, I really dislike the greenwashing, lack of ethical manufacturing, and slim size range. But on the other hand, they are comfortable and affordable! I also just find them to be really, really comfortable — especially the organic cotton bikinis.
Will I continue to wear them? Yes. Will I buy more? Probably not.
Ready for even more Underwear Thesis reviews?? Catch up on my previous reviews:

AUDEN FROM TARGET UNDERWEAR REVIEW
So to kick things off this time, I’m sharing my thoughts on truly one of the most requested brands of this entire project: Auden from Target! I can’t even tell you how many times I’ve been asked to review Auden. So I’m really glad to finally have this review published — you’ll have to let me know what you think!

EVERLANE UNDERWEAR REVIEW
New year, new underwear! I wanted to start off by thanking you for your patience in the last few months. I really did want to share even more Underwear Thesis reviews, but like… moving, renovating, the holidays, a tree falling on/around our house… it’s been a LOT. So, thank you. Lets move onto the reason you’re here though: my unfiltered thoughts about Everlane underwear! It was really fun to get back into these reviews and really dig into the details of each pair. I hope you enjoy this Everlane underwear review and learn a lot!

THUNDERPANTS UNDERWEAR REVIEW
Wow, it’s the last day of Underwear Thesis… where did the week go?? I hope you’re loving the reviews and learning a ton. As this series evolves, I want to incorporate more small businesses who are entering into the underwear game and today’s review is a great example. Today we’re breaking down the details of my full Thunderpants underwear review — this is my most requested brand to check out, btw!

PACT UNDERWEAR REVIEW
Here’s the thing about reviewing different pairs of underwear: you can only get so creative with the photography! But seriously, I am running out of ways to photograph underwear. Anyways, this week’s Underwear Thesis review is all about Pact, an organic clothing company. I think they are most known for their super soft organic basics. They definitely have a loyal fanbase and I got tons of requests to try them out because I think a lot of people curious! So if you’re in that group, keep reading to get the full scoop of my Pact review.

THIRDLOVE UNDERWEAR REVIEW
Today let’s focus on ThirdLove! This underwear brand was the first package in my shopping spree to arrive and I actually really liked them right off the bat. I laid out the judging criteria in this post, so let’s dig in. If you’re new to the blog, definitely check out that one, as well as my post about what to look for when shopping for underwear. They’re both great for getting you started!

What do you think of this Felina underwear review?? Leave a comment and let me know!