Under the proposal, launched ahead of the 2016 Welsh Assembly election, all children from the age of three would be entitled to an initial 15 free hours of childcare, before rising to 30 hours a week.
Parents could take up the hours at private and voluntary early years settings as well as schools.
Plaid Cymru would invest an additional £100m over ten years to deliver the policy.
Currently, three- and four-year-olds in Wales receive 10 hours of free childcare a week. Children aged two to three from the most disadvantaged families are entitled to 12.5 hours under the Flying Start programme.
Plaid Cymru says its proposals could save parents around £100 per week and help close the attainment gap between children from advantaged and disadvantaged families, as well as help parents return to employment or take on more work.
According to the party, parents in Wales pay among the highest costs for early years provision in the developed world, with childcare fees having risen by 40 per cent in Wales since 2011, compared to an average UK increase of 32.8 per cent.
Launching the policy at a nursery in Carmarthen, shadow education and skills minister for Plaid Cymru Simon Thomas said, ‘Research shows that done properly, a good childcare system helps tackle the link between poverty and poor attainment, helps improve the economy, and helps take families out of poverty. That’s why Plaid Cymru’s plans are important – this isn’t just about improving children’s educational output, but is about strengthening the economy, giving parents greater flexibility over work, and about putting money back in parents’ pockets.
‘Families in Wales have a rougher deal than elsewhere in the UK. Childcare is more expensive here than the UK average, there is less available childcare in Wales than in England, and parents in Wales are entitled to less free childcare than other UK nations.
‘Many parents are not able to work as much as they want to because of childcare constraints, so it’s important we give parents the opportunity to work more. Good quality childcare along with early-years education can provide children with a good start in life helping them develop their cognitive skills as well as social benefits.’
Purnima Tanuku, chief executive of National Day Nurseries Association (NDNA), said, ‘Plaid Cymru’s election pledge to offer 15 free hours to all three and four-year-olds, increasing to 30 free hours in the longer term, is big news for families with children aged under five and the early years sector in Wales.
‘Nurseries have so much to offer – the right facilities, expert knowledge and experience of under-fives and their educational needs plus the flexibility to serve working families who need childcare from 8am, or earlier, to 6pm.’