Period. FAQ

How do I flow?

Everybody. You don’t even have to be on your period, or even have a period. We also have adaptable underwear for people with different abilities, as well as boxers, to ensure that everyone who gets a period feels comfortable. We cover sizes XS to 6X so that we can reach everybody (and if ever you think we need to have more sizes, then just let us know at

Period. is highly absorbent underwear, designed to absorb your period, so you don’t have to use tampons or pads. It has a four layer towel technology with a special wicking layer, which means that any period blood is soaked up super fast and you won’t have a ‘wet feeling.’ After you’ve used a pair, you rinse them under the tap, throw them in your laundry, then they’re ready to use again.

That’s the whole idea.

Everybody periods differently so it’s tough to be exact. Our average time is about 8 hours on a heavier flow day. Though some customers need to change after 3 to 4 hours, and others can go up to 14 hours (lucky them!). As your period gets lighter, one pair can take you through the day and night (just like regular underwear). But again, everybody periods and Periods differently, so you need to take one cycle to figure out exactly how often you need to change. Start with a conservative estimate on your heavy days, and check in on your Period underwear after 4 hours. If you still feel good, give it another hour. Keep going until you figure out your limit. Here at Period, we find we need between 3 to 4 pairs on the first two heavy days. And if you leak, please forgive us! Just this once. (Remember how many tampons you have forgiven). Treat the ‘leak’ as a gift and note the hour of your leakage. That is the best indicator of your ‘flow threshold’ how long the underwear will last for you.

How many pairs you need per period is decided by two things. Firstly, do you want to wash any pairs during your period and reuse them during that same period? And what’s your flow threshold? 

Just to give you an idea (but remember everyone periods differently) - here, we tend to use three to four Heavy Period. pairs for Day 1, and the same for Day 2. Then for Day 3, 4 and 5, and sometimes 6 we wear one pair of Medium Period. a day. Now, if we don’t want to wash any pairs during a period and reuse them, that’s around eight pairs of Heavy Period. and four pairs of Light Period. But if we do wash them and reuse them in the same period, we can cut that down by half. So four pairs of Heavy Period. (wash three before you go to bed on Day 1, and dry overnight for the next day) and two pairs of Medium Period. (wash and dry after use).

Everyone periods differently. When you try your first pair of Period., you’ll need to figure out how many hours they can last for on a heavy day. That’s your flow threshold. You know how you just know with a tampon and pad? And how intuitive it is when you need to change? Well exactly the same thing goes with Period. underwear. On that first try, check in on your underwear every hour or so and see how they’re doing. You’ll know when you’ve hit that threshold, then just remember that time, so you can build your Period. plan around it.

Absolutely. We knew the biggest barrier to people trying Period. underwear would be a fear of leaking, so we purposefully designed Period to be super-super absorbent. Bring it on Day 1 (but easy on the cramps)!

You know how by now with a tampon or pad, you’re just pretty intuitive? Well that’s what happens with Period. underwear. You just feel that moment of change brewing. The padding can start to feel a little heavy or like it’s not absorbing any more. That means it’s reached its limit. 

Let’s really think about the idea of leaking. Leaking is something that we’ve been taught is horrific by companies that make tampons and pads (which, by the way, we’ve all regularly leaked with). Using Period. means shaking off some of that programming: what you experience with Period. might feel like leaking, but is actually flowing. And our hyper-absorbent four layer is ready to catch it all. But if you do leak the first time you wear us, don’t freak out. You are welcome to write to us and vent, but that first leak with Period. is actually a gift. A gift!?? Yup. You see it’s the best indicator you can get of your ‘flow threshold’ - that’s how long you can wear Period. for before it leaks. Once you know that, you’ll never leak again. Ps here’s our address if you need that vent:

Just take The Period Bag with a fresh pair of underwear in your bag. When you feel like it’s time to change, go to the bathroom, take off the worn pair, put it in your baggie, wrap it up and put on the new pair. You can rinse and wash the worn pair later at home. 

Yes we are and proud of it. Here’s how we make that possible: Before going into production, each Period. fabric is tested by Intertek Labs to ensure the fabric passes both CA PROP 65 And a PFAS panel. The CA prop 65 panel tests for over 400 toxins and carcinogens, in addition to a wide range of PFAS. Then, during production, we consumer test the bulk product at UL labs. These tests include color fastness, shrinkage, performance and another round of heavy metal and PFAS testing. Each piece of Period. fabric has to pass these tests otherwise they don’t make it out of the door. We have been tested by numerous consumer groups and have just received a validation from UL of ‘PFAS NOT DETECTED’ for all products. Now let’s ask tampon what’s in their product? 

Yes! And thank you for asking because this is a really important conversation. We’re one of the safest ways you can period. Our underwear is made without PFAS. We rigorously third party test every production, and reject any materials that don’t meet our standards.When we started Period., knowing it was a new category, we were advised to hold ourselves to the highest standard possible in the category. Guess what? We discovered that there weren’t any real high standards - so we created our own. So that you could have the safest flow possible.

And BTW, do you know the FDA has 400 defect warnings about tampons? Yikes.

I have questions about my order

Click here to check your order status!

Here is our breakdown on all standard shipping!

First order is Free Standard Shipping in the contiguous US - you just need to sign up for our newsletter ( link ) or listen, use a new email if you have already ( wink wink ) 

Hawaii, Alaska and PR are now a FLAT RATE of $10 for standard shipping ( whoohoo ) 

Back to Free - any purchase over $55 USD / $75 CAD qualifies for Free Standard Shipping for Canada and all of the US. (Customs and duties not included for Canada ) 

Canada - Guess what - you’re now a glorious $15 USD / $21 CAD Flat Rate for standard shipping. And listen, sure you still have customs and duties, but we’re still going to save you over time from all the money you’d spend on disposables. So be wonderful Canadians - we’re trying our best here, eh!

Terms and Conditions

All free shipping is standard shipping. Offer subject to change.

Orders that exceed the dimensions and weight restrictions for standard shipping may incur an additional shipping charge.


USPS First Class 6 - 20 Business Days, Priority Mail 6 - 12 Business DaysFedex Ground  3 - 10 Business DaysFedex Priority 1-3 Business Days


USPS First Class 1 - 6 Business Days, Priority Mail 1 - 4 Business DaysFedex Ground  1 - 5 Business DaysFedex Priority 1-3 Business Days

Yes! We have a formidable customer service department (run by amazing people who period) that will answer any question about Period. and who can help with styles/sizes. You can write to them right now at or SMS them.

Why should I switch to Period.?

The average period on tampons and pads costs $240 a year. Period. costs about $60 a year (five pairs) and can last anywhere from 2 years to 10 years depending on how you take care of them. So let’s say they lasted for 5 years, you’d spend only $60 as opposed to $1200 on pads and tampons during the same amount of time. Wow.

Yes! It’s non-disposable - just like your regular underwear, so unlike tampons and pads, it won’t be sitting on a landfill for the next five hundred years. Also what’s good for the Planet, is good for you. Though we can’t scientifically say it, a lot of customers say they have experienced less cramps and a much happier flow. Go ahead. Try it and see.

See for yourself. A fun way to really measure it is to put all the waste that you’d accrue from a normal period in a sink as you use it. All the plastic. All the stuff. As Karla, our co-founder says ‘it feels like Christmas morning.’ And not a good one. That will be your last waste-filled period. Remember this every time you have a waste free period with Period. Feel free to high five anyone around!

I have more questions...

After you’ve worn your period underwear, rinse them with water.

You’ll see some blood come out, but it’s okay - it’s your blood.

Throw in the laundry bag until laundry day.

Or rub with some soap, hand wash them and hang them up to dry or low tumble dry.

Or… if you really don’t feel like rinsing in the basin under water, you can either rinse them in the shower with you or throw them straight into the laundry with everything else.

Yes, you can! We recommend tumbling dry on low, but whatever happens, happens. 

Some brands use sprays and finishes in their fabrics to control smell, but these chemicals contain heavy metals we're just not sure about. Until the anti-microbial technology has a natural alternative that's seriously non-toxic, we're going to sit that option out. Fresh period blood doesn’t have a scent that carries. You might smell it on yourself, but think about it - have you ever smelt somebody else’s blood? Also, we’re human. Smells are OK.

Before we answer that, let’s talk about what ‘fresh’ actually means. Are we talking about the astringent ‘fresh’ that decades of advertising has systematically told people they have to be. Or are we talking about feeling clean and not leaking? We’re that kind of fresh.

Dr. Sade, our Chief of Medicine, says:

“Good news - the material will absorb the liquid that typically surrounds the clot. While the material cannot break down the semi-solid part of the clot, this portion is natural and typically no cause for alarm*. We would recommend a quick *tap tap* of toilet paper on the crotch of the panties when we're in the bathroom to help collect and break down those more solid portions.

(*If you feel you are passing large blood clots (quarter-size or bigger) and your doctor is not aware, be sure to inform him or her to be thorough)”

Thank you Dr Sade!!!

Yes! We designed Period. for periods and everyday pee leaks. Sneeze, laugh hard, star jump - we’ve got you!

Of course. Although are you sure you want to use a product that is more leak-free than a tampon to back up a tampon? If at first you don’t feel comfortable taking the risk, you could try Period. underwear one day when you’re at home or just at night. You’ll see.

You know the period gush? That inexplicable moment that usually happens when you wake up on day two and get out of bed. Well, as soon as you get out of bed on day 2, change your underwear. Your new pair will handle the gush and give your nighttime pair some respite. 

You can rinse your underwear in the shower.

We see a gold medal in your future…

From the moment you start your period, and even before. Period is just like regular comfy underwear, designed to catch any leaks. If you’re a period first timer, try it out before you even get your first flow just to get used to it.

Please do! A lot of stuff comes out both during and after your pregnancy. A lot of our customers rely on us for support during their Postpartum experiences.

We are a community-inspired company and many of our customers have asked for a thong so we made one. It can absorb a light amount of period blood (about 4 tablespoons) and is designed for those days and occasions when your period is light and you just want to feel like you again. Work out in it, go for dinner in it, do whatever you want but do not attempt a heavy day in the thong.


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