How do I know? Well, I tested some myself, polled Cosmo editors for their expert recs, and combed through reviews to find the best water bottle sling bags and bring them straight to you.

I got the Béis Sport Sling in Olive—the brand's newest ... Unlike the Béis bag, the Calpak Water Bottle Holder doesn't have multiple zippered compartments or space in general.

YETI just revealed its newest drop — three Cayo backpacks that are going sell out as fast as their sister style did. Here's ...

The Calpak Water Bottle Holder was the most prominent ... But the Corkcicle Crossbody Water Bottle Sling Bag, a neoprene crossbody bag with an attached bottle pocket, is cleverly constructed ...

While not technically a sling or a holder, this purse attachment ... this eco-conscious bag will keep your hiking supplies safe, and your water bottle easy to access. If you’re more of a runner ...

Compact yet spacious, the Peak Design 7L Outdoor Sling Bag makes traveling light easy — whether you're hiking a trail or capturing the perfect shot.