REI Co-op Rainier Rain Jacket — Kids’ Review

The REI Rainier is our top pick for kids’ rain jackets, and it earned that spot in real conditions — a rainy February music festival in Steamboat Springs, Colorado, where Cypress, 4, wore it for full days in wind and sustained rain and stayed completely dry. Of all the jackets we tested, this one has the most thoughtful details: a soft collar lining, dual cuff closure, adjustable hood, and nylon-lined pockets that actually wipe clean. It runs large, which is the one thing worth knowing before you order.

4.8/5.0

Best kids' rain jacket overall

REI Co-op Rainier Rain Jacket – Kids’

The most thoughtful design we tested. Soft neck, dual cuffs, adjustable hood — the one we'd buy if we were only buying one.

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Sizes: XXS–XL (fits approx. ages 4–14) | Waterproof: Yes — HydroWall 2.5L, seam-taped, PFAS-free DWR | Windproof: Yes | Weight: 7.4 oz | Fabric: 100% recycled ripstop nylon, bluesign approved

Is the REI Co-op Rainier Rain Jacket waterproof?

Yes — genuinely, properly waterproof and windproof. The HydroWall 2.5-layer membrane is seam-taped throughout and treated with a PFAS-free DWR finish. We tested it in sustained wind and rain at Winterwondergrass in Steamboat Springs, Colorado in late February, and Cypress, 4, stayed completely dry for the full 15-20 minute walk from our condo to the festival grounds — and then for the duration of the festival itself. That’s a full day in real rain and Colorado wind, not a parking lot drizzle.

Where we tested the REI Rainier

Steamboat Springs in late February had no business being rainy. It should have been a ski town in peak winter. But Colorado had an unseasonably warm winter and Steamboat in particular got hit with rain instead of snow, which made Winterwondergrass a wet, windy, genuinely challenging outdoor experience. We were staying in a condo about 15-20 minutes from the festival grounds — far enough that we were fully outside, in it, for every walk. We loaded Cypress into the wagon, zipped him into the Rainier, and did that walk multiple times over the weekend.

He wore it without fussing. That alone tells you something. Rowyn, 5, who was with us for the weekend, was less thrilled about her jacket situation — but that had more to do with being five and done with the whole cold-rainy-festival situation than anything to do with the gear. Cypress just put the Rainier on and got on with his life, which is the goal.

REI Rainier features — what actually stood out

The details on this jacket are thoughtful in a way that makes you notice when they’re missing. Start with the collar: it’s lined with a soft, fleece-like material that keeps the waterproof shell fabric off the neck. On a cold wet day when a kid is wearing a jacket for hours, that matters enormously.

The zipper storm flap runs the full length of the jacket with Velcro dots — not just a loose flap, but one that actually seals. At the top there’s a hook-and-loop tab for extra security right at the chin. The hood has a slight visor, elastic on the sides for a snug fit, and a Velcro adjustment at the back so you can dial in the fit over a winter hat or cinch it down in wind. Both adjustments in one hood.

The cuffs have both elastic and Velcro — that dual closure is genuinely useful for sizing up. Buy bigger, roll the sleeve, Velcro it down, and you’ve got a jacket that fits over a puffy and still keeps the wrist sealed. Two zippered pockets with a smooth nylon interior — nylon, not mesh — which wipes clean when the inevitable happens. Reflective strips on the arms and back.

The jacket carries a small interior care tag with a note encouraging you to pass it down when your kid grows out of it. The last line: still got some adventure in me. That’s not marketing. That’s a jacket that knows what it is.

The 100% recycled ripstop nylon fabric is bluesign approved — meaning it meets strict environmental and safety standards throughout the supply chain.

What doesn’t work on the REI Rainier

It runs large. We ordered XXS for Cypress at 4 years old and it was big. On this jacket specifically, don’t size up. If you’re between sizes, size down. That’s the opposite of our usual advice for kids’ rain jackets.

It’s also a shell only — no insulation. Cold rain without a layer underneath means a cold kid. The windproof construction helps, but it won’t generate warmth on its own.

How to care for the REI Rainier

Machine wash cold with all zippers and closures secured. No bleach, no fabric softeners — both degrade the DWR coating. Tumble dry low, which helps reactivate the DWR finish. If water stops beading after washing, a cycle in the dryer on low usually fixes it. If it still doesn’t bead, apply a spray-on DWR treatment like Nikwax.

Does the REI Rainier pack down?

It doesn’t stuff into its own pocket, but rolls up easily into a compact bundle. At 7.4 oz it disappears in a bag or a wagon basket.

REI Rainier sizing guide

We tested XXS on Cypress at age 4 — it ran large, closer to a 5T fit. Size down or order your kid’s exact size. The dual cuff closure and hood adjustment manage extra room well if you do land between sizes.

Who is the REI Rainier best for?

Families who want one great kids’ waterproof and windproof jacket for real conditions — Colorado thunderstorms, Pacific Northwest school days, outdoor school, camping, music festivals that don’t cancel for rain. The soft collar lining makes it genuinely comfortable for all-day wear. If we were only buying one, this would be it.

Pro tip: Size down or order your kid’s exact size. This jacket runs big.

How the REI Co-op Rainier compares to other kids’ rain jackets