Officials from various government departments will take part in a month of sustained industrial action from mid-December.
PCS union members working for the Home Office, Border Force, Department for Transport and Defra are seeking better pay and conditions.
Ports, borders and all areas of transport, including driving licences, will be affected as some workers operate throughout the month while others leave for shorter periods.
PCS general secretary Mark Serwotka said the exact details of the action would be announced closer to the time to give the government as little notice as possible.
He said ministers should deal with the causes of the dispute rather than making contingency plans.
He added: “PCS members are angry.
“They helped keep this country running during the pandemic and in return have been treated appallingly by this government.
He said: “With inflation now at 11.1%, it is inconceivable that they would be expected to face another pay cut in real terms.
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“With tens of thousands of members on the poverty pay, it’s no longer about belt-tightening, it’s about choosing between heating and food, and that’s simply not acceptable for the government workforce.”
The union wants a 10% wage increase, pension reform, job security and guarantees that layoffs will not be cut.
Serwotka repeated a suggestion he made last month that co-ordinated action could be taken in the new year by joining other unions, including those representing rail workers, university teachers, firefighters, NHS staff and Royal Mail workers .
He asked Cabinet officials to “come back to the table ready to meet our demands.”