Are 866, 877, and 888 toll free numbers?
Yes. 800, 888, 877, and 866 are all toll free prefixes and work the same in the United States, Canada, Puerto Rico, and the U.S. Virgin Islands. The 800 prefix was the first available, so you will often hear toll free numbers interchangeably referred to as "800 numbers". The 888, 877, and 866 prefixes were released later to meet increasing demand from small businesses.