The Nigeria Civil Service Union is a trade union representing workers in the Nigerian Civil Service.

The union was founded in 1978, when the government of Nigeria merged the following trade unions:

Nigerian Civil Service Union Ministry of Defence Civil Employees' Union East-Central State Messengers' and Allied Workers' Union Government Coastal Agency Workers' Union Eastern Nigeria Internal Revenue Staff Association Eastern Government Stores Workers' Union Co-operative Inspectors' Union of Eastern Nigeria Eastern Nigeria Bailiffs' Union Association of Federal Produce Officers of Nigeria Union of Telephone Operators' Attendants ECS Civil Service Technical Workers' Union Civil Service Technical Workers' Union of Nigeria Treasury Workers' Union of Eastern Nigeria South-Eastern State Treasury Staff Association North-Central State Civil Service Union Northern States Civil Service Union North-Eastern State Treasury Staff Union Federal Statistics Northern States Workers' Union Kano State Junior Civil Servants' Association Nigerian Federal Office of Statistics Workers' Union South-Eastern State Ministry of Education, Non-Teaching Staff and Allied Workers' Union Union of Western Nigeria Co-operative Inspectors

The union was a founding affiliate of the Nigeria Labour Congress. By 1988, it had 205,397 members, but by 2005, this had fallen to 100,000. It has had a long-running demarcation dispute with the Association of Senior Civil Servants of Nigeria.

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