The Public and Commercial Services union said almost 250,000 workers will take part in a rolling series of walkouts and protests as it steps up its campaign against budget cuts.
A 24-hour strike will be held on March 20, the day Chancellor George Osborne presents the Budget to Parliament.
Further national stoppages will be held, of varying durations and targeting different parts of the civil service, with dates to be announced at a later stage.
Other forms of disruptive industrial action will also be held, and the PCS said it will seek to co-ordination with other unions on pay and pensions.
More top news
"Vibrant and funny" teenager opted to donate her organs after becoming seriously ill in a "final act" of generosity.
Three men have been sentenced to a total of 31 years for their role in a 'crash for cash' plot which led to the death of a great grandmother
She met with the families of children who must stay near the hospital.