Some 20,000 staff providing advice on tax returns will hold half-hour walkouts on Monday over alleged moves towards privatisation.
The officers, who work at call centres and enquiry offices, are also planning more action on 31 January, the deadline for online self assessment returns.
The Public and Commercial Services Union said the strikes are against the government's hiring of two private firms in trials to run call handling.
HMRC denied any plan to outsource jobs.
More:
http://www.bbc.co.uk/news/business-16568190
The officers, who work at call centres and enquiry offices, are also planning more action on 31 January, the deadline for online self assessment returns.
The Public and Commercial Services Union said the strikes are against the government's hiring of two private firms in trials to run call handling.
HMRC denied any plan to outsource jobs.
More:
http://www.bbc.co.uk/news/business-16568190