Replace the cap of your stainless steel bottle with an Onia Filter Straw and start enjoying healthier, truly filtered water everywhere you go.

Don't have a compatible stainless steel bottle yet? Get a FREE Onia bottle when you order now.

Built for your bottle or ours

Fluoride water filter

The Onia Filter Straw is compatible with:

  • 27 oz/40 oz Klean Kanteen Classic
  • 21 oz Hydro Flask Insulated
  • 27 oz Onia bottle (FREE at checkout)

Just replace your stainless steel bottle's ordinary cap with the Onia Filter Straw and voila. Your bottle is hacked.

Not sure if you have the right bottle? Check our Fit Guide.

Onia Filter Straw

Kick contaminants where it hurts

Our patented, BPA-free filter makes tap water taste great and instantly removes up to 99.99% of tap water contaminants as you sip.

The best in portable filtration

Most filter bottles and pitchers only remove some aesthetic chlorine. The Onia Filter Straw will also protect you from heavy metals, trace pharmaceuticals, pesticide runoff, and other common menaces of municipal tap water that can build up in your body over time.


  • Meets and exceeds NSF Standards 42 and 53 for contaminant reduction
  • Anti-Fluoride Technology removes 90% of fluoride
  • Intelligent Filtration Technology keeps health-essential minerals in your water, like magnesium, iron and electrolytes
  • Filters made in USA
  • 100% BPA-free, 100% FDA approved food grade, anti-microbrial materials
  • Sip through our patented flip-up straw cap. No more unscrewing caps or biting mouthpieces.

What it Removes

  • Chlorine >99.99%
  • Bromodichlormethane >99.40%
  • Chloroform >98.52%
  • MTBE >99.80%
  • 4.4-DDD and DDT >98.80%
  • Chromium 6 >99.87%
  • Fluoride >90.00%
  • Lead >97.50%
  • Mercury >99.60%
  • Radon 222 >99.00%
  • Total Suspended Solids >99.00%


Say "bye" to bottled water

With a hacked bottle, you'll never have to buy an overpriced bottle of water ever again. That's great news for our planet, your wallet, and even your health, since bottled water has its own share of contaminants.

Fresh filters sent straight to your door

When you order an Onia Filter Straw, we automatically send a replacement filter every four months for $24.95 each (free S&H). That's just 20¢ a day for a lifetime of freshly filtered water.

How it Works

Be a clean water hero.

For every fresh filter we send to your door, we provide four months of clean drinking water to someone in need.


Giving Back

Lack of access to safe drinking water is crippling communities all over the world. Waterborne diseases are a leading cause of mortality, and women and children are forced to spend more time gathering water than receiving an education.

Now you can help provide these communities with the pure drinking water they so desperately need.

It starts with our filter subscription program, which you will automatically be enrolled in when you purchase an Onia Filter Straw. For every 4 month replacement filter we send to your door, we will provide 4 months of clean drinking water to someone in need through our partnership with Thirst Relief International.

We will keep you updated on the clean water success stories you've helped create. Ounce by ounce, we can break cycles of poverty and even save lives.

About Thirst Relief International

Thirst Relief is a non-profit organization that brings safe water to communities in the developing world using local labor. Every penny they receive goes straight to their cause. Their successful relief projects have inspired hope in all of us that we can someday end water poverty.

Charity water

Ready to hack your bottle?