An Act of Senedd Cymru (Welsh: Deddf gan Senedd Cymru), or informally an Act of the Senedd (Welsh: Deddf gan y Senedd), is primary legislation that can be made by the Senedd (Welsh Parliament; Welsh: Senedd Cymru) under part 4 of the Government of Wales Act 2006 (as amended by the Wales Act 2017). Prior to 6 May 2020, primary legislation was formally known as an Act of the National Assembly for Wales (Welsh: Deddf Cynulliad Cenedlaethol Cymru) or informally, an Act of the Assembly.
The power to make primary legislation was conferred on the assembly following the 2011 elections as a commencement order had been passed in the Assembly by simple majority prior to dissolution. The activation of part 4 legislative powers was as a result of a "yes" vote in the 2011 referendum held in Wales. When the power to make Acts of the Assembly commenced, the Assembly lost the ability to make Measures under part 3 of the 2006 Act. Existing Measures will remain as law unless repealed.
