Yes, Alexa skills are free.
However, sometimes there are premium features to an app that accompany a skill, and you have to pay for these features. This is entirely optional and all of the basic Alexa commands and skills have no charge.
About the Author: Dr Teri Fisher
Dr Teri Fisher, dubbed “The Voice Doctor,” is a unique blend of award-winning TEDx and keynote performer, physician, podcaster, author, educator, and leading authority on all things voice technology. Teri, known for his laid-back, friendly, personable, and upbeat style, breaks down the complexities of voice technology to its simple parts and is your guide to navigating the world of voice. A Voicebot 2020 “Top 17 Influencer in Voice”, Soundhound “Top 40 Voice AI Influencer”, host of the Project Voice 2020 “Flash Briefing of the Year”, finalist for the 2020 “Voice AI/Commentator of the Year” and 2019 “Commentator of the Year”, Alexa Champion, and Bixby Premier Developer, Teri is a leader in voice technology around the globe.