Whitepages.com, AnyWho.com and 411.com offer search tools to find the owner of a fax number as of 2015. The websites provide the name associated with a fax number for free.
To reverse search a fax number on Whitepages.com and 411.com, click Phone, enter the fax number with the area code, and then click Search. Information about the number, such as name, location and carrier, is displayed on the next page.
To do a reverse search of a fax number on AnyWho.com, click Reverse Lookup, enter the fax number, and then click Find. The resulting page shows the name and address of the owner of the fax number.