Over 80% filed online, a 10% increase on last year's figures. Employers are required to inform HMRC by 19 May of details of their employees' tax and national insurance payments in the last financial year.

Employers with 50 or more employees must file their returns online, and HMRC is keen to encourage small employers using traditional filing systems to switch to the online version.

A spokesperson for HMRC said:

"We will continue to encourage smaller employers to file online by listening to their requirements, and meeting those requirements whenever we can and I hope those small employers who file using the traditional media are encouraged to make the switch to online services."