If you're looking to give your Yeti cup a good clean you might be inclined to put some bleach in there. After all bleach can be great a getting rid of mold and other stains. But can you bleach a Yeti cup?
The answer is actually surprising:
You CANNOT put bleach in a Yeti cup as it will cause the cup to rust. Both chlorine bleach and oxygen bleach (hydrogen peroxide) corrode the stainless steel that Yeti cups are made from. Use other cleaning products instead and keep your Yeti away from bleach.
Yeti actually state in their care instructions and on their rambler FAQ page:
Do not use bleach or abrasive cleaners.
What Happens If You Bleach a Yeti Cup and Why?
When you put choline bleach in a Yeti tumbler cup the bleach will cause the cup to begin rusting. Bleach is corrosive to stainless steel and makes it rust quickly.
But why exactly does this happen?
Chlorine bleach contains the active chemical sodium hypochlorite (NaOCl) which according to the BSSA is a dangerous pitting and corrosion hazard for stainless steel.
If you let me get a little sciencey on you the reason is actually quite interesting.
Stainless steel is “stainless” and resistant to rust because it contains chromium. The chromium reacts with the air creating a protective layer of chromium oxide which stops air and water reacting with the iron and creating rust.
This protective layer is invisible to us but it works extremely well at protecting stainless steel from degrading.
The problem with bleach is that it dissolves the chromium layer allowing the iron to react with oxygen and rust.
This scientific paper sums it up nicely:
Constant exposure of stainless steel to chemicals containing chlorides will cause the chromium component on the surface to dissolve. This permits the free iron in the stainless steel to react with oxygen to form rust
Can You Used Hydrogen Peroxide in a Yeti Cup?
Hydrogen peroxide is another form of bleach, but rather than being chlorine based it's oxygen based.
It's considered to be not as strong as chlorine bleach but it still has many uses from dying hair to removing laundry stains to cleaning surfaces.
Unfortunately it turns out that hydrogen peroxide is also corrosive to stainless steel and thus it will cause your Yeti tumbler cup to rust if you leave it in there for too long.
They have done tests on this and shown that hydrogen peroxide does cause pitting corrosion in stainless steel.
What Should You Use To Clean Your Yeti Instead of Bleach?
There are a variety of different cleaning products you can use on a Yeti cup instead of bleach.
If your cup has tea and coffee stains, smells or maybe even has some rust there are a few different things you can do to bring it back to life and make it as good as new again.
The easiest method is to simply use a cleaning tablet. You can see my review of the Yeti cleaning tablets but they are quite expensive and there are cheaper options out there on Amazon.
With these cleaning tablets you simply put it in your cup, fill it up with water and let science and chemical reactions do their magic.
It's a really simple way to give your Yeti a refresh and a good clean.
You can also use more natural cleaning products like vinegar and baking soda and also giving it a good scrub with a mildly abrasive cleaner like a magic eraser can also help to remove built up dirt, grime and stains.