England and Wales
In addition to a permit to fish, any angler aged 12 years or over, fishing for salmon, trout, freshwater fish or eels in England (except the River Tweed), Wales or the Border Esk and its tributaries in Scotland must have an Environment Agency rod licence.
Money from the sale of licences helps to fund work managing fisheries. If you are caught fishing without one, you are cheating other anglers and could be fined up to £2,500.
There is no requirement in Scotland to have a licence to fish, however an angler must have the legal right or permission to fish. There is no salmon or sea trout fishing on Sundays anywhere in Scotland (except the Border Esk in Dumfriesshire which is dealt with under English law, since much of the river is in England).
It is now illegal to keep a salmon caught before 1st April or on some rivers categorised by the Government. All fish whether dead or alive must be returned to the water. Some rivers have local later dates, for more details go to Scottish Government website