You resist the temptation to blow it on a holiday or a new lounge suite. You will either use it to pay down your mortgage or put it into your super fund. But which one will deliver the best benefit for you in the lead-up to retirement?

This scenario was put to two financial advisers who crunched the figures on both options. Putting it into super came out in front in both cases, largely because of the tax impact of super's concessional tax treatment.

Taking the $5,000 bonus or pay rise example, Centric Wealth's Anne-Marie Esler says the salary sacrifice into super is treated as a concessional contribution, which means it is taxed at 15 per cent, leaving a net $4250 going into the fund to earn a return.

Mortgage payments on the other hand are made from post-tax dollars and so the amount left after marginal tax is paid to pay down the mortgage is reduced to $3425, $2925 or $2675, based on the respective marginal tax rates of 31.5, 41.5 or 46.5 per cent.

David Simon, executive financial planner with Westpac, looked at the $10,000 pay rise or bonus options and also concluded putting it into paying down the home loan is tax inefficient.

He cites the scenario of a 50-year-old looking to retire at 60 who has a $250,000 mortgage repayable over 30 years.

Assuming the super fund earns an average 7 per cent a year, a person earning $60,000-$90,000 a year will have $126,000 more in super after 10 years.

That money can then be applied to paying down the mortgage with tax-free dollars when they reach 60 and can access super. However, if the bonus or pay rise is applied to paying down the mortgage, his figures show the person earning $60,000 will have reduced the mortgage by a further $99,000 at the end of 10 years.

The person earning $90,000 will have reduced it by a further $85,000 over the same period. The difference is due to the lower after-tax dollars left to pay down the mortgage at the $90,000 salary level.

Simon says that if the strategy is tweaked further, and the principal repayment part of the mortgage payment also goes into super as a salary sacrifice (leaving only the interest payment to be made), the end result is an even higher super benefit - and more tax-free dollars to repay the mortgage at 60.

Neither example takes into account the impact of the timing of the payments into super or market volatility.

It could be that in a falling sharemarket putting the money into super might wipe out the equivalent of the bonus or the pay rise in any one year. Yet both planners point out that super is a long-term investment and they have not factored in differing market conditions affecting the result.

Esler adds the advantage of paying down the mortgage as opposed to putting money into super is that super benefits are preserved until a condition of release is obtained, whereas additional mortgage payments will increase equity in the property and this may be withdrawn at a later stage for other investments.

She concludes that while concessional super contributions are mathematically superior to a mortgage reduction, there are other factors to consider apart from just the financial benefit. Super contributions become more attractive the higher the individual marginal tax rate.