Period Underwear?! – FLUX Undies Review

Hello and Welcome!

Yes, that’s right, we are once again delving into the world of periods. As I said in my previous post, I know that talking about periods might make some people uncomfortable, but periods aren’t some weird or taboo thing that we shouldn’t talk about!

As you can see from the title, today I’m going to specifically be discussing and reviewing some period underwear. This is underwear with a built-in pad feature which you can wear instead of traditional pads or tampons (or whatever other period products you use/wear).

I’ve always been interested in these kinds of products so I was excited to see that FLUX Undies were looking for bloggers to review the products. I reached out to them once I saw their Twitter post and they said they’d be happy to send me some to try in exchange for a review.

I’m very aware of the waste that comes from pads/tampons and the negative impact on the environment, so a reusable option really appeals to me. Personally, I use pads because I’ve never got on with tampons, and I find them pretty uncomfortable sometimes so I thought that having underwear with a pad built in might minimise some discomfort.

I chose to receive their ‘Classic Bikini’ style of this underwear, in black. These retail for £27.95, hold four tampons worth (which as a pad wearer means nothing to me), and come in a range of sizes from XXS (UK size 4-6) to 4XL (UK size 28-30).

Personally, I am a size 12 in bottoms so I asked for a size medium (which states it is a 12) but was sent a size small (a 10).

Before we get into the main part of the review and my experience, I just want to give a little background about who FLUX Undies are.

About FLUX Undies

On their ‘our story’ section under their about tab, it says the following:

‘We bleed. We sweat. We shouldn’t let anything hold us back. That’s why we reinvented underwear. So you feel fearless, every day. Founded by women. For everyone. We knew there had to be a better way. After years of spending every month scared of embarrassing leaks, and dealing with uncomfortable disposables, FLUX founder Paige Fashoni knew there had to be another alternative to simply ‘putting up’. So we made it. Our founder Paige hit the drawing board, after endless research and testing, FLUX was born in 2017. A three-layer dreamy fabric combo that sicks moisture, absorbs fluid, and prevents leaks. All built-in to a super soft pair of underwear. Five styles. Two colours. Seven sizes. No more leaks We’re no back up. You can wear FLUX alone, and #bleedfree. One super absorbent panel, paired with our superior leak proof backing, means you can get on with your day, comfortably and confidently.’

They also have a ‘By You, For Her’ by which they provide a reusable cloth period pad to a girl in need when a pair of FLUX underwear is bought.

Let’s talk Maths

Before we get into my full thoughts let’s talk about the maths of this product, since I’m sure you’re going to want to know if you’re saving any money (as well as the planet of course) if you switch to this period underwear.

The underwear varies in price from £25.95 to £28.95 per pair, but we’ll discuss it based on the price of this product at £27.95 and it states you need 2-3 pairs per cycle – personally I would say you’d need more pairs than this unless you’d want to be washing a pair approximately every 12 hours (it states each pair can be worn for up to 12 hours) during the length of your period.

However, let’s take their recommendation of 3 pairs to get through a cycle to do this maths, and round up the price of one pair to £28.00.

This would mean it would cost £84.00 for the three pairs. A realistic average cost for periods in the UK is roughly £128.00 per year so this would mean a saving of roughly £40.00 per year if this underwear were to be used instead of the sanitary products available on the high street.

This is assuming that the underwear lasts one year before needing to be replaced. Of course, it may last longer (I’ve seen some articles say that they can last 2 years). It all depends on how well you take care of them, but if they last one year you’re looking at around a £40.00 saving, and if they last two years you’re going to be pushing up towards a £160.00 saving!

This saving doesn’t take into account the fact you won’t be ruining any underwear (the average person ruins 5 pairs of underwear a year due to periods) since the pad is part of the underwear.

Overall, this is a pretty good saving! This, of course, doesn’t account for the extra water you’d be using to wash the underwear if you’re washing them every 12 hours in a washing machine but this is quite hard to work out and wouldn’t equal the amount saved.

Claims & Care Instructions

On the product page for the Bikini underwear, the product has the following claims/description:

‘Our bestselling Bikini offers full coverage and protection, keeping you fresh ‘n’ dry when you need it the most. Bikini features a soft lace trim that keeps your undies looking so cute, you might even forget you’re on your period! Wear for up to 12 hours Holds 20-25ml, or four tampons’ worth For periods, leaks & incontinence Great for day & night Sustainable and OEKO-Tex Fabrics’

I think more importantly, the following information is given in regards to care instructions:

‘RINSE Give ’em a quick rinse WASH Chuck ’em in a mesh laundry bag before popping them into the machine on a cold wash DRY Hang to dry outside or inside! PS: Don’t use bleach or fabric softener.’

My Experience and Thoughts

Bikini FLUX Underwear When I first received these, a couple of things stood out to me.

Firstly, they are so cute! The lace at the top is really beautiful and you definitely wouldn’t think that these were period pants! I’m really glad that they added this cute little lace accent to still make the underwear pretty and attractive.

Secondly, they’re incredibly soft. Honestly, it’s such a nice material. It’s super plush and well-made and feels unbelievably good – it’s hard to get across just how great they feel! I have no underwear that feels this nice and, when you know it’s for your period, you’re thankful about how comfortable they feel.

The crotch area feels quite bulky, which is to be expected since there’s in-built padding to absorb the blood. However, it isn’t bad and it isn’t very noticeable (like it is when you wear a ‘normal’ pad) when you’re actually wearing the underwear.

As I mentioned at the beginning, I asked for a size 12 but was accidentally sent a size 10 (I should have really mentioned it to the brand when the underwear came so that’s my fault). When I initially pulled them out, and tried them on, I thought that the 10 would be okay, as they seemed quite big, however as time went on with me wearing them I found that they were definitely too small. Due to the added material in the crotch, I found the underwear was tight on my legs in the joints, so I’d definitely recommend going for your normal size. Due to how soft the material is, the underwear did feel really nice everywhere apart from on my legs so I do think it would be great if you had the correct size for you. I’m a bit of an awkward size to be honest – some clothing items I need in a 14 if they don’t have stretch, some in a 12, my most worn jeans I need in a 10, honestly sizing is a nightmare for me! If you’re between sizes, or an awkward size like me, then I’d recommend sizing up as the additional material can make it tighter around your legs.

However, sizing issues aside I really liked these! I wore them overnight since this is the time I find wearing a pad most uncomfortable. Although I bleed more during the day, due to lying down at night I find it’s more likely to be messy (I always wear two pads so it covers fully from front to back). It was really nice to wear these and not have to worry about ruining a pair of underwear, or your sheets. They cover everything really well and are super absorbent, without making it feel like the crotch is being weighed down. It’s really nice to be able to just throw these on without having to faff around with pads, worry you’re going to bleed through, or have that horrible crinkly feeling/sound when you move. 

After trying some other sustainable period products, I think I would specifically use these at night and not during the day. As I said, wearing a regular pad (or two) at night can be pretty uncomfortable so it would be nice to throw these on and not worry about it. However, during the day I think I’d still prefer to use a pad product over these due to the washing situation. 

You need to rinse these out my hand before you put them in the washing machine and it’s not very enjoyable. Someone I know who uses a similar underwear product said that she puts them in the shower, which is a great idea. I just think the extra step of rinsing them isn’t for me. For extra comfort at night (and therefore a better night’s sleep) I’d definitely pick these but for use during the day, I would prefer to use a different sustainable product.

I really want to be more sustainable with my periods. Pads are something that I use more frequently than any other disposable product. I feel like sanitary products are something that people don’t really think of when they think of being more sustainable but it’s something I’m definitely interested in and this product is a great step in that direction.

If I had more money I would definitely invest in a few pairs of these to wear at night because I do really love them and I think they’re a great product, however I’m really not in a good place financially at the moment so I can’t justify purchasing a couple of pairs.

Overall, I think these are a really cool product and I’d definitely recommend getting them if you’ve been contemplating using this kind of product. I know it can be difficult to make the switch but if you’re thinking about it then these are a great choice! They’re really well made and are super soft and cute – your period doesn’t always have to be about wearing weird ugly underwear that you don’t care about ruining.

If you would like to check out what styles of underwear they do, purchase some for yourself, or just find out some more information about the brand, then you can do so here.

So this bring us to the end of this review, I really hope that you enjoyed reading it! If you did enjoy then please leave a quick like on this post. Also be sure to follow my blog if you aren’t already, I post cruelty free beauty and lifestyle content.


Charlotte (Multibendybeauty)   Follow me on Instagram

Check out my previous posts!

My Favourite Blog Photo & Flat Lay Props (giving you my secrets)
97% Natural Hair Products – Noughty Haircare Review
The Body Shop Shower Gels and Creams Review

2 Comments Add yours

  1. These sound like something I’d only wear at night, even though they work, I’d still be super scared of leaks in the day!


    1. I know what you mean! I think because they’re black it’s difficult to tell where the blood is/how much there is (you can get them in another colour that is lighter though). I’m sure it something you’d get used to judging though. I just don’t think I’d like the bulk during the day, especially if it’s hot, it’s already not great wearing a pad when it’s hot out lmao x


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s