For the best balance of price, reliability, and film freshness, these are the top recommended retailers:

: A top-rated specialty merchant known for handling film with care. They stock a wide variety, including and limited-edition frames . Choosing the Right Film for Your Camera

: Generally considered the best source for fresh film . Buying direct ensures the film hasn't been sitting in a non-climate-controlled warehouse for years. They also offer a rewards system and bulk bundles (3-packs or 5-packs) that can make them cheaper than other retailers in the long run. B&H Photo Video