Article 12 of the Charter of Fundamental Rights of the EU has a freedom of association:
> 1. Everyone has the right to freedom of peaceful assembly and to freedom of association at all levels, in particular in political, trade union and civic matters, which implies the right of everyone to form and to join trade unions for the protection of his or her interests.
But I don't think the person I'm replying to above was thinking of labour unions. ;)
I think you'll find this libertarian "right to enter into any contract for anything" doesn't exist in EU law.
The Charter of Fundamental Rights doesn't list it. It does list the right to protection of personal data.