On May 7, the people of Wales will go to the ballot box to elect a total of 96 Senedd Members across 16 constituencies.
These representatives will then get the chance to make laws that affect people across Wales.
However, Wales only has powers that have been devolved from the UK Parliament at Westminster. Matters that remain under the control of the UK Parliament are known as reserved powers.
While Wales is responsible for areas such as education and healthcare, matters including immigration, justice and policing, and defence remain under the control of Westminster.
Understanding the difference between Senedd and Westminster powers is important when deciding where to raise concerns about issues affecting you and your community.
So what will the new Senedd Members elected on May 7 actually be responsible for?
The development of Senedd powers
In 1999, the National Assembly for Wales, as the Welsh Parliament was then known, was established as a single ‘corporate body.’
The Assembly could only pass secondary legislation in areas already devolved through the Government of Wales Act 1998 – meaning that Westminster remained responsible for passing primary legislation for Wales.
The Government of Wales Act 2006 changed that, giving the Assembly the power to create legislation on devolved matters in 20 areas, including education, healthcare, and the Welsh language.
As a result, the confusingly named Welsh Assembly Government (which was effectively a committee of AMs) became a legally distinct entity called the Welsh Government.
In 2011, a referendum on the powers of the National Assembly was held where voters were asked whether the Assembly should have full-lawmaking powers in the 20 fields where it has jurisdiction.
The country voted yes and the Welsh Assembly gained the power to create Acts of the Assembly without needing UK Parliament’s approval.
The Wales Act 2017 then moved Wales from a conferred matters model to a reserved matters model, as is used in Scotland, meaning the matters under the control of Westminster are explicitly listed and any matter not listed is devolved to the Senedd.
Further powers given to Wales as a result of the Wales Act 2017 included the creation of the Welsh Revenue Authority; the ability to raise or lower income tax by up to 10p in a pound; and the power to extend eligibility to vote.
As of April 2026, the Senedd holds significant law-making powers over most aspects of health and social care, housing, education, local transport, economic development, social services, language and culture, the environment, and local government.
The Senedd also has some tax-raising powers including control of local taxes, taxes on property transactions, and the power to vary income tax rates in Wales.
However the Senedd still has fewer powers than the Scottish Parliament and the Northern Ireland Assembly, particularly as the Senedd has no power over policing and justice.
