Good Halloween costume stores besides Spirit?

I've heard good things about Danny's Trix and Kix in Spring. Be aware that it's going to be busy for Halloween and the Texas Renaissance Festival.

I like shopping at Miccostumes and Fashion Nova because they offer a wider selection of costumes. Their quality is generally good, but I do wish they had physical stores. If you prefer to shop locally, you might want to try Party City or visit some second-hand stores. I've found that with a little creativity, you can create a costume that's just as good as the pre-packaged Spirit costumes, often for a lower price.