I have seen that student loan interest rates are likely to go up.

I was in two minds about whether my son should go to university funded by a loan in the first place, so would it be worthwhile paying it off in full as soon as he graduates? NF, via email

When the decision to go to university is made, taking out a student loan seems obvious. It is only after graduating that most take note of the risks which include variable rates of interest, the uncertainty of graduates' earning prospects and the potential for the Government to change the terms of the deal in the future.

If you have money available with which to pay off your son's loan at once, there are a number of factors to consider.

The ups and downs of paying it off right away

The way student loans work is that if a graduate doesn't earn enough during their career, any outstanding after 30 years is written off. Repayments are tied to income.

So you could calculate, based on expected earnings in any likely career, the cost of the loan over three decades. We have a calculator to help you do that (scroll down).

Broadly, if they are unlikely to earn enough to get close to repaying it in full, plus interest, they might be better off simply servicing the debt until the remnant is written off.