The number of victims of identity theft rose by 57% last year, figures from fraud prevention service Cifas suggest.
The data, taken from 261 companies in the UK, suggests fraudsters are increasingly getting people's personal information from social media sites.
Cifas said Facebook, Twitter and LinkedIn had become a "hunting ground" for identity thieves.
It said there were more than 148,000 victims in the UK in 2015 compared with 94,500 in 2014.
A small percentage of cases involved fictitious identities but most fraudsters assumed the identity of a real person after accessing their name, date of birth, address and bank details. More than 85% of the frauds were carried out online.