In Wales, councils are responsible for funding and overseeing schools.
But in England, Mr Osborne's plan will mean local authorities will cease to have a role in providing education.
Academies are directly funded by central government and head teachers have more freedom over admissions and to change the way the school works.
It is a significant development in the continued divergence of schools systems on either side of Offa's Dyke.
And although the Welsh Government will get extra cash to match the money for English schools to extend the school day, it can spend it on any devolved policy area.
Ministers have no plans to follow suit.
At the moment, governing bodies are responsible for setting school hours and they need ministerial permission to make significant changes.
There are already more than 2,000 secondary academies in England and its extension to all state schools is unlikely to shake the Welsh Government's attachment to what they call a "community, comprehensive model" for schools.
It rejects claims that freedom given to academies can help drive up standards, and it points to academy-free Scotland as the best performing school system in the UK.
Education Minister Huw Lewis said there was "very little evidence to suggest" academies have a positive impact in driving up standards and Wales would not be following the model.
"The Tories have wasted hundreds of millions of pounds on academies and free schools and as the Chancellor finalises his budget plans to slash vital services even further, he is committing them to wasting even more on a failing endeavour.
"We have no plans to introduce the chaos and waste of academies and free schools here in Wales."
None of the main parties in May's Assembly election - including the Welsh Conservatives - have said they want to introduce academies in Wales.
Owen Hathway, NUT Cymru's policy officer, called the academy plans for England "scandalous.".
"There is no evidence that academies work, no evidence that they raise standards, no evidence that they offer better quality education and no evidence that they are what parents and communities want," he said.
"Certainly a commitment to comprehensive education is something we would want, and indeed expect, all parties to hold firm to in their manifestos for the forthcoming Welsh election."
But the Welsh and English schools systems are still linked by a joint arrangement for teachers' pay and conditions.
Academies are not tied to these pay scales so in effect Wednesday's announcement will take all English schools out of the system and raise questions about the viability of an England and Wales pay and conditions structure.
There is already growing momentum for the devolution of teachers' pay and conditions.
Originally sceptical, the Welsh Labour Government is now broadly in favour.
Some teaching unions remain opposed because of concern that Welsh teachers would end up being paid less than those in England.
Mr Hathway said teachers were concerned it could lead to regional pay.
"At the same time we do of course recognise that the issue of pay is already becoming a grey area due to the negative changes we see taking place in England," he said.
But an even bigger difference between the schools landscape on either side of the border, appears to make separate arrangements for pay increasingly likely in future.
As Chancellor George Osborne announced all English state schools will become academies, the Welsh Government continues to reject the model here.