Getting access to data

Access through a letter

A person's hand hovers their mobile phone over a bar code in an energy bill.


Sending a physical letter to users with a printed code that they can scan to access information. For example, an energy provider might include a code on their paper bills, which customers can scan to find out more information.


  • It relies on someone having access to a specific address, limiting the risk it could be read by someone else
  • The code can be formatted for single use, so if it was used once it could not be used again
  • The letter helps the user understand what the code is for and what information can be accessed by scanning it
  • It requires little effort from users to get access, making it quick and simple


  • Letters can be lost, damaged and easily opened by others
  • Unless there’s secondary authentication after the code is scanned, anyone could access information
  • The user needs a level of digital literacy to be able to scan a code with their device
  • Not all phones come with this capability
  • Some barcode scanner apps might require huge amounts of unnecessary permissions