Currently employers operating restricted stock unit plans usually tax the employee’s vesting gain as general earnings. From April 2016, such gains must instead be taxed as securities option income, so far as the employee has a conditional right to acquire securities (rather than cash). Either way, gains accruing to international assignees who are UK tax liable for only part of the earnings period will be time apportioned for income tax. The switch will nonetheless have significant and largely adverse consequences for liability to NICs, and for the employee’s CGT and remittances position.