If Scotland votes ‘yes’ in September’s referendum, its independence will have a profound effect on the UK corporate tax system. UK businesses will have to adapt to doing business in two countries rather than one, with additional burdens created by a new border on the Tweed. And corporate tax policy in Scotland may well develop in a very different direction to the rest of the UK. Few tax departments will want to devote significant time now to an event which is still likely to be (marginally) defeated at the polls, but some affected groups with much disentangling required between their Scottish and ‘rUK’ businesses may want to start planning for this now.