Years ago, older generations would laugh at Gen Z-ers and millennials, saying, “you always have your phones in your hand!” Well, now the etiquette is as follows: phone in one hand, reusable water bottle in the other.

So long are the days of plastic water bottles. Not only are they the absolute worst to stash inside your work tote — (1) for the planet, and (2) because they don’t keep your water ice-cold for very long — but reusable water bottles are the wave of the future. Namely, Stanley and Owala.

Stanley’s years-long success isn’t so much about selling a bottle to transport liquids in; it’s more so the trendy, “cool girl” lifestyle. Of course, anyone can use its tumblers, but TikTok has named the brand as being every woman’s hand-piece.

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As a full-time product reviewer who has been using my Stanley for years, I decided to give Owala a try. After all, it’s a recent Amazon best-seller and, considering how much I love bringing my water with me on the go, I wanted to finally see what all the hype was all about.

Ahead, you’ll find my full, in-depth review and a brief summary of how I tested each brand. At the end of the day, your favorite may differ from mine, with your final decision largely influenced by aesthetic, design and color range, too.

The Stanley Quencher H2.0 FlowState Stainless Steel Tumbler with Straw Lid is one I’ve been drinking from for years, the model of choice among many who work from home or want their tumbler with them on the nightstand to have with them before bed and throughout the night (aka, me).

Sure, plenty of people love the Stanley name but, if the brand wasn’t etched on its exterior, I’d still say it’s worth it. I will say, it’s my “house tumbler” as I find it’s not the best for on-the-go use as it doesn’t have a fully covered lid. In fact, it flooded the inside of my work tote when I was driving to a coffee shop, a mistake plenty of people have made and a learning lesson on my end; as mentioned, it’s my “house tumbler.”

Despite all this, it’s still my go-to option for chilling atop my standing desk or on the floor next to my sectional sofa, while I’m wrapped in a weighted blanket watching TV.

Its well-made exterior and excellent temperature preservation make it a win-win in my book. Its quality lid and straw are nice features as well, both of which are easy to clean. While it’s quite heavy when completely filled — a surefire weapon, to say the least — it’s worth the buy if you’re looking for a tumbler with a large capacity.

We love an underdog moment, and I must say, the Stanley IceFlow Stainless Steel Tumbler with Leak-Resistant Flip Lid is my favorite tumbler that I’ve tested. It doesn’t hold as much water as the acclaimed, best-selling Quencher H2.0 but it’s the ideal size, especially if you’re on the go.

It’s built exactly like Stanley’s more popular jug but has a genius flip-top lid that is spill-resistant. It’s also $10 cheaper which doesn’t seem like a big deal but is more accessible to shoppers who don’t want to breeze into the $50 mark. Additionally, it’s the perfect size.

The minor con to this tumbler is that its lid usually takes a bit longer to clean, largely because the straw doesn’t detach. However, this tumbler has the it-factor and I usually tell everyone IRL, “I actually like Stanley’s flip-top tumbler more…”

Stanley, who? Owala is coming after the major tumbler brand’s throne with its FreeSip Insulated Stainless Steel Water Bottle. What’s lovely about this option is its aesthetic and ergonomic design. It’s clad with a sportier look and integrates more shades into its overall travel bottle. For instance, its ivory shade has hints of red and mustard yellow to add pops of color while standing tall to its sleek silhouette.

The budget-friendly pick is also less than $25 on Amazon and — drumroll please — is the best for travel. Its pop-and-lock lid made my jaw drop at first and, while there are more “steps” to actually unveiling the drinking spout, it’s not a hassle by any means.

Conveniently, it easily fits in most backpack side compartments. Unlike Stanley’s which are a bit too large at the base, this one hugs pocketed mesh fabrics perfectly. It was like Owala’s product designers were like, “Let’s solve students’ and athletes’ major issues.” If I were a college student, this would be my pick, though I still reach for it at home and when I’m on the go for work.

Similar in performance and, in part, design, Stanley and Owala do hone have some key differences worth mentioning:

Overall, the Stanley IceFlow Stainless Steel Tumbler with Leak-Resistant Flip Lid is my overall winner. For an excellent at-home tumbler, there’s nothing quite like the Stanley Quencher H2.0 FlowState Stainless Steel Tumbler with Straw Lid, and the Owala FreeSip Insulated Stainless Steel Water Bottle is a great option for car travel and on-the-go activities, like playing pickleball or heading to the airport.

After reviewing both Stanley and Owala side by side, here is the testing criteria I used:

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