Interest rates for those under the new student loan regime are set to rise dramatically in September following an unfortunately-timed surge in the Retail Price Index (RPI) to 1.6pc in March, the monthly figure used to calculate interest on the loans.

A new system was introduced in 2012 with rates on loans starting at RPI and rising to RPI plus 3pc, depending on earnings.

The March RPI figure sets the rates and this is applied the following September.

The figure for last year was 0.9pc, applying to those whose income is £21,000 or less. The maximum rate was 3.9pc, paid by those earning £41,000 or more, with a sliding scale in between.

This March RPI was at 1.6pc as calculated by the Office for National Statistics, meaning that from September the new base rate of interest will be 1.6pc, sliding up to a maximum of 4.6pc.