The use of personal webmail applications for work purposes has increased, with 85 per cent of people aged 25 years or under admitting that they send work related emails or documents to or from personal email accounts.

Research of more than 2,400 corporate global email users by Mimecast found an emerging ‘Generation Gmail', who it said: “Displays a particular frustration with corporate email restrictions, complaining that mailbox sizes are too constrained and that they will readily ‘work around' using personal email to be as productive and flexible as possible.”

More than half (51 per cent) of those surveyed said if they had an unlimited work mailbox they would be less likely to send work emails to personal accounts. It also found that over 300 work-related emails are sent per person via personal accounts each year. Typically around half of these emails contain attachments, meaning that the average employee aged under 25 years will send approximately three emails a week that may contain potentially sensitive information outside of their corporate environment.

Daniel Axsater, CEO of CronLab, said: “So many people use webmail for professional purposes so blocking it is harsh but it is recommended to have processes and rules within the company and how you control them can be by blocking, but you can get statistics on who people have been in contact with.

“It is important to communicate within the company but this is not a job for IT, it is for HR and they need to communicate policy. Employees are very smart and will find ways around it.”

Nathaniel Borenstein, chief scientist at Mimecast, said: “Email is a vital channel, indeed the preferred choice, of communications within companies today. Although more fanciful headlines would have us believe that email is on the verge of extinction, the reality is that email is embedded within company culture and will remain a core communication channel for some time to come.

“However, unprecedented change is afoot as a new generation of people who have had lifelong exposure to technology enter the workforce, bringing with them unique challenges in the provision and management of email and other technologies for companies.

“The proliferation of social networks and mobile devices has transformed the communications landscape within companies; employees increasingly mix and match technologies, using devices and platforms interchangeably to find workarounds that maximise their flexibility and productivity. Employers need to work out what they are going to do in the face of this cultural shift.”

A previous survey by Virgin Media Business of mailbox limitations found that 69 per cent of workers cannot send or receive emails larger than 10MB in size, and 89 per cent are unable to send or receive emails in excess of 15MB, leading workers to utilise personal webmail services as an alternative.