The union is taking its 'Keep Public Services Public' message to Europe's biggest street festival with a float and a colourful band of masqueraders.
Dave Prentis, general secretary of Unison, said: 'The Notting Hill Carnival is the London party and Unison would not want to miss the float. It's a chance for our members to go out and enjoy themselves, and at the same time promote our public services.
'We want to stop creeping privatisation gaining a strangle hold on our public services and we want to shout out our message - Keep Public Services Public. We know that the privatisation culture prevalent throughout Britain, is not popular with the public - it has been tried and has failed to match up.
'The public put high quality public services at the top of their agenda and we want to keep them there. Our message is clear - no to creeping privatisation and yes to well funded, democratically accountable public services.'
A range of Unison paraphanalia will be handed out to festival-goers including whistles, frisbees, fans and torches.