That is one of the messages employers are getting from the Inland Revenue over the next three weeks.
From May 2004, large employers must start paying tax and other deductions electronically. And they must start sending end of year returns (P14 and P35 data) online by May 2005.
Employers who are medium-sized in 2006 must start online filing by May 2006.
Small employers do not have to start online filing until later. But those who start filing online early can get up to £825 tax-free from the Revenue over five years, starting with 2004-05 end of year returns.
From today, the Inland Revenue is writing to 1.6 million employers to tell them whether they are a large employer (250 or more employees), a medium-sized employer (50-249 employees), or a small employer (fewer than 50).
When an employer must start to online file, and pay electronically, depends on whether the employer is large, medium or small.