It's different in Scotland - Part 2: Income tax and transaction tax
The Scottish Parliament has for some years had the ability to vary the rate of income tax, (but not the detailed rules around it) for the benefit of the Scottish Exchequer. For some years they chose not to do so.
In recent years this has changed with 2017/18 being the first year in which a differential arose. The impact in 2017/18 was relatively limited as a result of freezing tax bands as a result of which most taxpayers requiring the services of an accountant have been £400 worse off as a result of their residency in Scotland.
Someone once commented to me, there are actually more registered methodone users in Scotland than there are additional rate taxpayers. I haven’t checked the accuracy of this statement but additional and higher rate taxpayers do tend to pay around 90% of all the income tax, so making the relatively easy choice to move south of the border even by a relatively small percentage of them could have a significant impact on revenues.