A toll-free telephone number for international calling. A UIFN charges the cost of the call to the called party. Standardized by the ITU-T, the numbering convention for UIFNs is 800 + 8 digits. See also ITU-T and toll free service.
"UIFN." YourDictionary, n.d. Web. 08 June 2018. <http://www.yourdictionary.com/uifn>.
UIFN. (n.d.). Retrieved June 08th, 2018, from http://www.yourdictionary.com/uifn