The starting point for employers', employees' and self-employed national insurance contributions will be maintained at £110 a week despite the negative rate of inflation. But there will be an additional 0.5% increase in the employee, employer and self-employed rates of NIC from April 2011, alongside an increase in the point at which individuals start to pay NICs to protect the 15m people on incomes below £20,000. The change effectively doubles the changes proposed in the 2008 PBR.The upper earnings and profits limits for Class 1 and Class 4 NICs respectively will be maintained at their current level of £844 a week, and for the self-employed, the rate of Class 2 contributions will continue to be £2.40 a week. Class 3 contributions will also remain at their current rate of £12.05. In line with the increase in the amount of the state pension (also announced in today's pre-Budget report), the lower earnings limit and the special Class 2 rate for volunteer development workers that are linked to this level, will rise to £97 a week and £4.85 respectively. Today's announcement will, when added to those rises previously announced, mean that employer's NIC will rise from 12.8% to 13.8% and employee's rate will rise by 1% from 6 April 2011. These changes will apply to all employers and employees who pay NIC (essentially those earning more than £97 per week. This will mean that, for example, those employees on incomes over £150,000 will see their marginal rates (for income tax and NIC) rising from 41% now to 52% from 6 April 2011. Michael Carter, a partner at Addleshaw Goddard LLP, said: 'This is an additional tax burden on employers and employees, which was not highlighted by the chancellor in his speech. 'NIC is again being used as an easy means of raising tax income from employers and employees.'