An iPhone 5 was stolen from the Pack Horse pub, Hayfield, at around 10.30am on Thursday.
A dark skinned man, described as being either Asian or eastern European, aged mid to late twenties entered the pub.
The man pointed to a clip board he was carrying indicating he was deaf and mute and carrying out charitable collections. The staff member left to get assistance, leaving the bar and the phone unattended.
Anyone with information can call Constable Jonathan Owen on 101 or Crimestoppers on 0800 555 111.