In the pre-Budget report in November 2008, Darling announced the rate would rise to 45p from April 2011 - so today's announcement marks a twist for commentators who envisaged the changes might have been delayed.
Gemma McIntosh, head of stakeholder management at market research company TNS, told HR magazine: "This is bad news for employers and it is not a good time to raise taxes. Salary is king for engagement, even for high earners, and when salaries are reduced [through tax] the pay problem becomes more prevalent. It will put more pressure on employers to increase salaries."
And Pam Loch, founder and principal at employment lawyers Loch Associates, added: "This is a stealth tax. The Government thinks it will go relatively unnoticed, but for some employees it will be noticeable and significant."
But Debbie Hayes, HR director at Vinci Park UK, added: "If the chancellor has plans to invest money in unemployment, there will have to be give and take and the cost of beating unemployment will have to be shared among the workforce. We can't stick our heads in the sand - we have to understand we need to pay towards this."
Commentators agree communication between HR and employees will be key to making sure staff fully understand the changes to their salaries when they come into place.
McIntosh said: "Managing tax changes is complicated for HR even with payroll systems. Staff need to be given the opportunity to ask questions regardless of what the changes may bring."
Budget 2009: Income tax hike for high-earners
The chancellor, Alistair Darling, has confirmed income tax will increase for high earners from 2010 but will affect those with salaries higher than 150,000 who will see their income tax on their higher earnings rise from 40p to 50p from April 2010.
