I'll take this opportunity to plug an instant decaf that recent surprised me (very pleasantly). Our hotel offered this for free in the lobby on a recent trip and I ended up buying some for travel purposes.

https://treelinecoffee.com/collections/on-the-go/products/in...

It's a swiss water method decaf instant that rivals some of the best cafe regular coffees I've had.

At stores/roasters, most will tell you the decaffeination method somewhere on the bag. If they don't it's probably not a brand that cares much about their decaf, so skip it. Make sure you go for as close to roast as possible - decaf goes off a lot quicker than regular coffee.

It’s actually hard to find brands that don’t use the water method if you buy “freshly” roasted beans. Unless you go super budget, medium budget beans like Peets, SF bay, etc use water process method.