Wanderlust World Wanderlust World No, it is not illegal. In England (and the wider UK), there is no legal obligation for any person or business to accept any specific form of payment—including Bank of England notes, Scottish or Northern Irish notes, coins, or Isle of Man currency.
While English traders can accept Manx notes, most do not because their banks may not exchange them easily, and staff cannot verify authenticity. Conversely, Bank of England notes are widely accepted on the Isle of Man, though not legal tender there either.
Payment acceptance is a matter of contractual agreement between buyer and seller. No one can be prosecuted for refusing Manx pounds—or any other currency—in England.