Are all serum natural deodorants created equal? That’s a big no. I tried one under each armpit for a week and here’s what happened:

I wore the same deodorant for years. Then I got pregnant. All my beauty products started to change. I began to embrace clean beauty. But I could not find a natural deodorant that I liked. The only benefit of not being able to workout during my pregnancy? I didn’t really sweat very much. So it wasn’t a big deal.

Then I had baby and postpartum night-sweats began. The minute I stopped breastfeeding I went back to my old deodorant. It was short-lived. My son decided his favorite place to snuggle was my armpits. And I couldn’t deny my newborn that comfort! It was back to natural deodorant for me. This time I decided to test two serum natural deodorants: Saltair 5% AHA Serum Deodorant and Kosas Chemistry Deodorant BO-Fighting AHA Serum. Here’s how they compare and which won each category:

Price: Tied

Saltair is $12 for 1.7 FL OZ and Kosas is $16 for 2.4 FL OZ. The price is so minimal that I would say that cost is a tie.

Aesthetic: Saltair

Aesthetic is a personal choice, of course. But I’m drawn to the minimalist, clean lines of Saltair’s recyclable glass packaging.

Scent: Tied

Scent is another personal preference. I’m obsessed with Saltair’s Santal collection. But both brands have unscented if that’s your thing. So I feel like it’s a tie.

Application: SALTAIR

It was significantly easier to apply Saltair’s serum deodorant, thanks to the rollerball applicator. Only a little comes out a time (which is a good thing!) because it allows you to roll it over a few times for a generous application. Kosas, on the other hand, came out so fast that some of the serum fell on the floor when I first applied it. My dog immediately licked it up. It’s clean beauty but still, it was definitely not ideal. Both serums rolled on clear and took about the same amount of time to dry. But Kosas’ formula felt stickier to me.

Effectiveness: Saltair

This is the most important category, in my opinion. They definitely both work in terms of controlling BO, which pleasantly surprised me given my previous bad experience with natural deodorants. But after 6 days I had to stop using Kosas. My left armpit (the Kosas armpit) got a huge red rash. It was so itchy! I took a break from any deodorant on my left pit for two days then started applying Saltair to both. My armpits have been happy, soft and not smelly ever since.

Availability: Kosas

Honestly my only complaint about Saltair is that the Santal and Fragrance Free serum has a waitlist. You can currently only get the serum in Pink Beach (it’s like a creamy coconut macaron). Again, I’m partial to the Santal scent. But in my book, good things are worth the wait! Kosas, on the other hand, is available on their site, as well as major retailers like Sephora, Nordstrom, BlueMercury and Revolve. So it’s definitely easier to buy.

Overall winner: Saltair

If you’ve read up to here, you already know that this was a no-brainer.

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