The government's Coronavirus Job Retention Scheme will launch on 20 April, according to HMRC.
The authority has informed tax agents of the launch date and requested their help during the application process.
Under the Coronavirus Job Retention Scheme, businesses are able to apply for government grants for employees' salaries up to the lower of 80% of an employee's regular wage, or £2,500 per month for three months from 1 March.
The scheme could run for longer if the social restrictions to help halt the coronavirus (COVID-19) pandemic remain in place.
In a note to agents, Jim Harra, CEO of HMRC, wrote: 'HMRC have been called on by the Chancellor to urgently direct financial support to where our citizens and businesses need it most. The first wave of this is the launch of the Coronavirus Job Retention Scheme.
'We need your help in this important work. Your influence and your reach across the business sector are instrumental in helping us ensure employers know what they can do to get ready to make their claim. Claims should not be made by phone, it will be an online service.'
Further details on the Coronavirus Job Retention Scheme can be found here.