Owala SmoothSip Slider (12 oz) Review

The last thing you need when running late in the morning is to slosh your morning coffee onto your white shirt. Been there, done that. But many travel mugs out there try to avoid that scenario and fall short, whether with faulty sliders, seals, or something else. So when Owala claims its SmoothSip Slider is leakproof, we’re naturally cautious, though curious. After all, we really liked its sibling, the Owala SmoothSip 20 oz, with the only caveat being that its spout didn’t close.

Now that we have a chance to try the same mug in a well-sealed design, we’re up for the challenge. Over the past few weeks, this cup has gone to work, high school, the store, and even college, as we used it for coffee with cream, water, and black coffee. Yeah, sorry, we drink a lot of coffee! How did it hold up? Fire up the French press for a new pot, and let’s dive in.

The Rundown

If you’re familiar with Owala’s SmoothSip, the SmoothSip Slider won’t look much different. It’s still made with stainless steel and has a pleasant powder-coat finish that’s pleasant to touch. We’ve got the Moonlit Shadow colorway, which has a blue base and a charcoal lid, with a few other accent colors, but you can pick it up in various shades and hues to match your personal vibe. The size and shape are cup-holder-friendly, with a vaguely squared-off bottom that turns perfectly round at the top. The Owala brand name parades vertically up one of the flat sides, but it’s small and subtle.

We’ve had no issues with scratching yet, though we know that’s possible with Owala bottles if you drop them (especially on cement, whoops!). Luckily, this one hasn’t taken a tumble yet, and we’re keeping our fingers crossed that it won’t anytime soon. We have yet to experience a negative impact on the bottle’s performance due to the drops and dings, though, so don’t worry if you’re a Dropsy Daisy. Some of us (this writer included) are, too!

The material is free of BPA, lead, and phthalates, so you don’t have to worry about harmful chemicals leaching into your drink when you put something hot inside. Plus, the stainless steel cup is insulated, and Owala claims that it can keep something cold for up to 24 hours and hot for up to six. Now, our coffee never lasts that long. Still, we can tell you that after pouring hot coffee inside, closing it up, and leaving it at room temperature for an hour before heading out to work and drinking in the car, it stayed at the same temperature. Your beverage will naturally cool off more quickly if you’re opening and closing the slider every few moments to take a sip, but it will stay drinkable for quite a long time.

Let’s talk more about that lid now. It’s made of super-smooth plastic that feels just as silky smooth as the original mug we tested. Owala does a great job of creating a slightly curved spout that molds perfectly to your lips when you drink from it. There are never any hiccups in the flow of liquid coming out of the spout, as we find with some other cups, which is appreciated.

There’s a seal between it and the stainless steel cup that is removable for cleaning and provides a color accent. That’s the same as on the SmoothSip, but what’s different is a round tab on top. It has a few ridges for your thumb to grip as you open it and a lip on the back to help you close it.

Simply pushing it toward the back won’t open it, though. You must push down on the slider to release any pressure and then slide it back. Don’t worry if that seems too complicated; it was for about a second and our testers quickly began doing it without a second thought. The only time it can be a tiny bit trickier is when driving on the highway, although, arguably, we maybe shouldn’t be trying to multitask like that. But when you have a lengthy commute, you want your morning coffee with you and you want it to be hot, so practice with the lid a bit before getting behind the wheel.

If you’ve finished your coffee by the time you arrive safely at your destination and have access to a sink, we recommend at least thoroughly rinsing it out to avoid any lingering taste. We know that’s not always possible, and there were times the SmoothSip Slider had to sit all day with coffee and cream residue inside. Life happens when you’re having fun, right? Well, if it does, you’ll just want to realize that there’s a chance of that coffee and cream flavor lingering in your water or next drink. That happens to the best travel mugs, but if you can wash it out as soon as possible, you’ll lessen the taste transfer.

Washing it isn’t quite as easy as you might think, though. We’ll start by pointing out that the lid is dishwasher safe but Owala recommends that you avoid putting the cup in the dishwasher to protect the powder coating. However, we think the best way to wash the lid is by hand because proper cleaning involves taking it apart so you can clean out every nook and cranny.

Owala admits that disassembly isn’t intuitive, and we agree. However, we also agree with their follow-up statement that it is easy. First, unscrew the lid from the cup. Then, open the slider, hook a finger behind the round tab, and pull. Don’t worry, you won’t break it, but it will pop off—it’s supposed to. Then, flip the lid over, and you’ll see the black slider. Turn it 90 degrees to the side, and it will release from the lid. After that, you can pull the seal out from around the lid to be sure you clean off any remaining coffee, tea, Powerade, or whatever else you decide to put inside.

After it’s clean and dry, just repeat the process in reverse to reassemble. We’ve been doing it daily throughout the testing period and have had no issues with it, nor have we had any problems with it developing leaks from removing and replacing the seal. However, we almost dropped one of the small slider pieces down the sink drain, so be careful as you hold the soapy pieces. That’s the only drawback of the system; without everything in place, it won’t stay leakproof.

And you wouldn’t want that because it definitely is. We filled it with hot coffee, made sure the lid was shut, turned it upside down, and then shook it multiple times on multiple days, and we could not get a drop to escape. We do not necessarily advocate packing a drink inside a bag, but you could with this bottle, and we are confident that your gear would stay dry as long as nothing bumps the slider. Since you have to press down before pushing it back, there’s a good chance that light bumps won’t open it anyway. As we said, we really don’t think you should put your coffee in your tote bag, but if you’re going to anyway, use this, not a Stanley Quencher H2.O FlowState Tumbler.

Packability

As we just mentioned, the Owala SmoothSip Slider is small enough to fit into bottle holders in nearly every bag if you want to go that route. However, you’ll most likely be using this cup on the commute, so you’ll be happy to know that we haven’t had an issue fitting it into different cup holders. It may take a little effort to wedge into some lined with silicone if you’ve ever seen those, but it seems like every bottle, even a skinny Hydro Flask, has that issue, so we’re not holding it against the SmoothSip Slider. If you have an average-sized cup-holder in your vehicle or rental car, you won’t have an issue using this mug.

At 10.65 ounces, it’s certainly not the lightest mug we’ve tested, but it’s not the worst, either. We sometimes have an issue telling when we’re about to take the last sip because it still feels like something should be inside, but that may be the tradeoff for the great insulation. Owala bottles, on the whole, aren’t the lightest bunch, and the SmoothSip Slider fits in with the rest of the family.

Quick Comparison

Probably the best comparison with the SmoothSip Slider is the Owala SmoothSip, which we have already tested and reviewed. The cups share many similarities, from the same feel and shape of the drinking spout on the lid to the same squared-off design at the bottom. Both are available in 20-ounce models, though the SmoothSip Slider’s smaller size is 12 ounces, whereas the SmoothSip’s smaller size is 10 ounces.

At the time of this review, they are available in different colorways, and the SmoothSip Slider has double the available shades to choose from—eight instead of four. So you may pick your mug based on color alone since fun designs are part of Owala’s draw.

However, the only significant difference between the two is in the slider. The SmoothSip lacks any closure and is spill-proof, so it won’t slosh out as you run up the stairs, but it’s not leakproof to save your computer if you knock it over. The SmoothSip Slider is most certainly leakproof, provided you close the slider. That also provides a bit more insulation if you pour in something hot or cold to enjoy a few hours later. The temperature will fluctuate more quickly on a cup without a sealed lid when compared with one that has one. The tradeoff is that there are more pieces to keep track of when cleaning it. You win some, you lose some.

So if you’re looking for a pleasant drinking experience and want the added assurance of a leak-free experience, you may want to give the Owala SmoothSip Slider a try. Since it’s comfortable to hold and sip from, we can’t think of a reason why you shouldn’t.