How Long Does Period Underwear Last and When to Replace It

How long does period underwear last? A THATDAY pair is made to last up to five years with the right care. How long yours actually lasts depends on how many pairs you rotate, how often you wear them and how you wash them. Here’s what affects the lifespan, how to tell when a pair is ready to retire and how to keep yours going for longer.

What affects how long period underwear lasts?

Period underwear lasts longest when it’s washed gently and shared out between a few pairs. Four things make the biggest difference.

• How many pairs you rotate. With 2 to 3 pairs, each one gets washed less often than if you only had one, so every pair lasts longer.
• How you wash it. Fabric softener, tumble dryers, washing hotter than 40 degrees and chlorine bleach can all shorten its life.
• How you wear it. A pair that’s worn on every heavy day works harder than one saved for spotting.
• The fit. A pair that’s too small stretches the elastic and the layers. Choose a size that fits comfortably without stretching the fabric or leaving gaps around the legs.

The materials matter too. Every THATDAY pair is sewn from 4 to 5 OEKO-TEX certified fabrics, quality threads and strong elastic, and handmade in Latvia, so it’s made for years of wearing and washing, not one season. We explain what goes into the price of a pair on Instagram, and in this reel we compare a 35 euro pair made in Latvia with a 15 euro pair made in China.

And it’s not just us saying it. One customer told us they’ve been using theirs for four years. Another bought a first pair five years ago and now has around six.

How do you know when to replace period underwear?

It’s time to replace a pair of period underwear when it no longer keeps you dry and comfortable, even after a proper wash. Look out for these signs.

• It doesn’t hold as much as it used to. If a pair starts to feel full much sooner than before, or you notice small leaks on days it used to handle easily, the absorbent core has done its job.
• A smell stays after washing. A cold rinse and a 40 degree wash should leave it fresh. If an odour stays even after the recommended cleaning routine and a vinegar soak, it may be time for a new pair.
• The elastic has gone loose. Period underwear needs to sit close to your body to work. If the waist or leg openings gap, it can’t do its job properly.
• The fabric is wearing thin. Holes or thin patches are clear signs the fabric is worn out.

Stains on their own aren’t a reason to replace a pair. What matters is whether it still absorbs well, fits comfortably and the fabric is in good shape.

How can you make period underwear last longer?

You can make period underwear last longer by washing it gently and giving every pair a rest between wears.

• Rinse it in cold water straight after wearing.
• Machine wash at 40 degrees with your other clothes, without fabric softener or soap-based detergent.
• Always air dry, never in the tumble dryer.
• Rotate at least 2 to 3 pairs instead of wearing one again and again.

That’s really all it takes. The full routine, including how to deal with stains and smells, is in how to wash period underwear the right way.

Is period underwear worth it in the long run?

Yes, for most people period underwear costs less than pads and tampons over time. When we asked our followers how much they spend on pads and tampons, most said around 5 to 7 euros a month. That’s 60 to 84 euros a year. In this short reel our estimate is closer to 100 euros a year, which adds up to around 500 euros over five years.

A starter set of 2 to 3 THATDAY pairs costs around 60 to 100 euros and is made to last up to five years. That can save you roughly 200 to 400 euros, and a lot less waste ends up in your bin every month.

Of course, your numbers depend on how heavy your flow is and how many pairs you end up with. If you’re still deciding, see how period underwear compares to pads, tampons and menstrual cups, or find out whether period underwear really works in our real tests.

So, how long does period underwear last?

A THATDAY pair can last up to five years. Rotate a few pairs, skip the softener and the dryer, and replace a pair when it stops holding like it used to or a smell stays after washing. Look at how it absorbs and fits, not at how many times it’s been washed.

Ready to build your set? Find out how to choose period underwear for your flow, or browse the full THATDAY collection.

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