I think you will find that's legal tender is a phase usually heard in England when businesses refuse to accept Scottish banknotes. Although the tender is indeed legal, traders south of the border can refuse to accept Scottish banknotes. However, they may soon have to accept them if a private member's bill is successful. The bill is being launched by Shadow Scottish Secretary David Mundell, it would require all providers of goods or services in the UK which accept Bank of England notes to also accept Scottish banknotes on an equal basis.  Three Scottish banks retain the right to print their own money - the Royal Bank of Scotland, the Bank of Scotland and the Clydesdale Bank but currently these notes are not backed by force of law anywhere in the UK.