Wales assumes full control of £1bn of business rates
The first new tax powers have been transferred to Wales, with the devolution of full control of business rates, worth nearly £1bn a year.
Finance Minister Jane Hutt said it gave ministers "new flexibilities" with an "important economic lever".
The small business rate relief scheme will remain similar to England's for at least a year, ministers have said.
Control of stamp duty land tax and landfill tax are due to pass to Wales in April 2018.
AMs also have the power to call a referendum on devolving some income tax varying powers.