If an authority does decide to charge, it can't charge you for the first £100 it costs to provide you with the information. So if the cost to the authority of providing the information is £100 or less, you will get it free of charge.
If the cost to the authority is more than £100, but up to and including £600, it can charge you 10% of the difference between these two amounts. So the maximum an authority could charge you would be £50. For example, if the cost to the authority is £200, it can only charge you £10 (10% of the difference between £200 and £100).
If the total cost to the authority is more than £600, it can refuse your request, but it should offer to advise you how to reduce the cost by making changes to your request. Authorities can choose to respond to requests which cost more than £600 if they want to, but they may first ask you to pay the full cost above the £600 limit.
Charges for environmental information may differ. Each authority must publish a schedule of its charges for environmental information.