The Rail, Maritime and Transport union said Mr Crow's family have asked for the funeral service at the City of London Cemetery and Crematorium to be private but have invited trade unionists, friends and colleagues of Mr Crow to line the route of the funeral procession.
The procession will include trade union banners and flags and will end at the cemetery gates.
But the RMT executive said it hoped for a huge turnout at the annual May Day march in London to honour Mr Crow, who died earlier this month at the age of 52.
Mick Cash, the RMT's senior assistant general secretary, said Mr Crow's death had rocked the trade union movement, both in this country and around the world.
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