The 5 Best Ways To Clean Your Nalgene Narrow Mouth Bottle

When I got my first narrow mouth Nalgene Bottle, I figured I could get away with just rinsing it out with hot water and dish soap. After all, I only used it for water. 

It didn’t take long to learn that I was wrong. 

After just a few weeks, my bottle started to smell mildewy, my water had a strange taste, and there was a slippery film on the inside of the bottle. Whoops. 

But the good news is, cleaning a narrow mouth Nalgene bottle is actually pretty easy once you know how. But it does take a little bit of extra effort than just rinsing it.

The best way to wash a narrow mouth Nalgene Bottle is by scrubbing with dish soap and a water bottle brush. If you don’t have a water bottle brush, you can fill the bottle halfway with hot water, some dish soap, and something to provide friction (like uncooked rice or a clean washcloth), then shake.

Soaking the bottle with water bottle cleaning tablets, diluted bleach, baking soda, or vinegar works pretty well too.

Narrow mouth Nalgene Bottles are a lot easier to drink from than the standard wide mouth bottles and my kids prefer them because they are worried they are going to spill the water out of the wide mouth bottles. Unfortunately, are also much harder to clean.

Luckily, with the right tools and approach, cleaning a narrow mouth Nalgene can be quick and easy too. 

Method 1: Use A Bottle Brush

The best way to clean a narrow mouth Nalgene Bottle is to use a bottle cleaning brush.

A soft-bristled or foam bottle brush is best because rough or abrasive brushes can scratch the inside of your bottle — which is a big problem because scratched plastic may leach more chemicals into your water or can cause your bottle to become cloudy through micro-scratches in the plastic.

I personally use and recommend this affordable 3-in-1 bottle brush set from Amazon. It's got a well shaped, long handle brush with medium firm bristles that won't scratch the bottle. Plus the smaller cleaning brush is perfect for getting into the narrow mouth lid and cleaning that out.

To wash your narrow mouth Nalgene with a bottle brush: 

1. Rinse out the bottle under hot running water. If there’s any stubborn, stuck-on drink residue, let the bottle soak for 15 to 20 minutes. 
2. Add a small amount of water and dish soap to the bottle (vinegar works well too if you prefer something more natural).
3. Wet your bottle brush and scrub the inside of the bottle, making sure to hit every surface and every corner. The top of the bottle near the neck can be particularly difficult to reach so pay extra attention there.
4. Wash the exterior of your bottle with a sponge or washcloth. Don’t forget to wash the cap, using a bottle cleaning kit if needed to get into all the cracks and crevices.
5. Once you’ve scrubbed every surface of the bottle, rinse away any remaining detergent under hot running water. 
6. Let the bottle air dry upside down on a drying rack. 
7. Store the bottle with the lid off and open so that it remains dry and doesn't grow mold

Like sponges, bottle brushes can harbor bacteria. Clean your bottle brush regularly and replace it every couple of months.

Method 2: Uncooked Rice

If you don’t have a bottle brush, the next best method to clean your narrow mouth Nalgene only requires some uncooked rice and dish soap (two things you probably have sitting around your house already).

This may sound a bit strange, but bear with me. 

1. Rinse your bottle out with hot running water. 
2. Pour about ¼ cup of uncooked rice into the bottle. 
3. Add a half bottle full of hot water and your cleaner of choice — dish detergent, vinegar, and baking soda all work well. 
4. Shake the bottle vigorously for two to three minutes. 
5. Pour out and rinse the bottle (empty the rice into the trash, not down the sink). 
6. Let the bottle air dry upside down on a drying rack. 

The reason this works so well is because the rice acts as an abrasive element, adding friction to the inside surface of your bottle when you shake it (similar to how a sponge or bottle brush helps clean).

Method 3: Stuff A Washcloth Inside And Shake

This one works on the same principle as the uncooked rice method. It adds friction when shaken, essentially scrubbing the interior of your bottle hands-free. 

The downside of this is the washcloth isn't as abrasive as the rice so it won't give it as deep of a clean. The plus side is it's a lot easier and less messy than having to deal with rice.

1. Rinse your bottle with hot running water. 
2. Wet a small, clean washcloth and add a dab of dish soap (or your cleaner of choice).
3. Stuff the dish towel into your Nalgene. 
4. Add about a quarter to a half bottle full of hot water. 
5. Shake vigorously for two or three minutes. 
6. Pour out your bottle. 
7. The washcloth should hang out of your bottle’s mouth enough to grab and remove when you hold it upside down. If not, you may need to fish it out with a pair of chopsticks.
8. Rinse the bottle to remove any remaining detergent. 
9. Air dry the bottle upside down and slightly angled on a dish drying rack. 

Make sure you’re using a clean washcloth each time. Reusing the same washcloth without cleaning it will introduce more bacteria to your bottle. 

The washcloth should be small enough to only fill about ⅓ of your bottle when stuffed inside. If it’s too big, it won’t be able to move around as much and won’t clean as well. 

Method 4: Soak With Diluted Bleach, Baking Soda, Or Vinegar

Bleach, vinegar and baking soda are all mold killers and so if you have found that your Nalgene bottle smells funny or has grown mold then this is something you should definitely do to kill the mold.

1. Rinse out the bottle with hot running water. 
2. Fill the bottle nearly full with hot water. 
3. Add a few drops of bleach (don’t overdo it) or a couple tablespoons of baking soda

NOTE: If you're using vinegar (which I usually do) then you should do a ratio of 50% vinegar to 50% water.

• 4. Shake well. 
• 5. Let the bottle soak for an hour or two if using bleach, or up to overnight if using vinegar or baking soda. 
• 6. Thoroughly rinse the bottle, especially if you used bleach.
• 7. Air dry the bottle upside down (and slightly angled) on a drying rack. 

I recommend only using bleach if your bottle is particularly nasty. Bleach corrodes plastic, so using it too often or using too much will damage your bottle over time. 

Vinegar and baking soda clean almost as well and are much easier on plastic.

Method 5: Water Bottle Cleaning Tablets

Water bottle cleaning tablets are an easy, natural way to clean a narrow mouth Nalgene. Most of them contain citric acid and when it reacts with water cleans your bottle for you.

If you don’t have any on hand, you can also use denture cleaning tablets (they’re almost the exact same thing).

1. Rinse your bottle under hot running water. 
2. Fill the bottle with hot water. 
3. Drop in a cleaning tablet. If it’s too big to fit into the mouth of your bottle, you can break it in half first. 
4. Let it fizz for 15 to 20 minutes. 
5. Empty and rinse the bottle. 
6. Air dry upside down and slightly angled on a drying rack.