From today it is illegal for tenants to be charge by landlords or agents for things like receiving an inventory, signing a contract or renewing a tenancy.
The sweeping changes are part of a new Welsh Government law that is, says the government, designed to "make things simpler and fairer for tenants."
It's estimated the change will save tenants, on average, around £200 per tenancy.
Payment can only be demanded from tenants for:
A payment in default (when a tenant breaches a contract)
Payments related to council tax
A television licence
Fixed penalty notices of £1,000 and a fines system will be used to enforce the new law.
A significant proportion of people in Wales live in private rented housing, and it is vital that they can be confident they are getting a fair deal. I want renting privately to be a positive choice which is accessible to everyone.