Jeremy Hunt’s promise that the Conservative manifesto will protect the ‘triple lock’ on the state pension is a desperate measure to appeal to the one group of the population whom the Conservatives feel they can rely on. But taxpayers will not be thanking him in a few years’ time. On the contrary, by keeping the triple lock – which increases state pensions by either the Consumer Prices Index (CPI), average earnings or 2.5 per cent, whichever is greatest – Hunt has abdicated any remaining fiscal responsibility and condemned the public finances to further ruin.

The triple lock is already costing taxpayers £10 billion a year. Since 2011/12 when the triple lock was introduced, the state pension has been uprated with inflation six times, average earnings three times and 2.5 per cent three times. Had it been increased by CPI every year it would now be worth £140.90 a week and if it had been increased by average earnings every year it would be worth £141.20 a week. In fact, the basic state pension in 2023/24 is £156.40 a week.

As it is, the state pension bill this tax year is £124.3 billion. Had pensions been increased by CPI it would be £114.3 billion and had it increased by average earnings it would be £114.5 billion. These are the figures for the basic state pension. The more generous new state pension which was introduced in 2016 – and so did not exist when the triple lock was introduced – is currently £203.85 per week.

The triple lock has the potential to make pensioners more reliant on the state than they are at present

The £10 billion a year cost of the triple lock is just the beginning though. It works like a ratchet. Under its terms, the state pension can never go down, and nor can it ever under-perform average earnings – although it can outperform them, as it has done in nine of the past 12 years. Eventually, if the triple lock is allowed to continue, we would reach a stage where pensioners received more income than the average working person. Already by 2050, according to the IFS, state pensions could be costing up to an extra of £45 billion a year in today’s money – a figure which takes into account the growing number of pensioners as well as the triple lock.

The longer the triple lock remains in place, the more the government starts to risk another unintended consequence. Working people will start to look ahead and wonder whether there is any need for them to make their own pension provision, given that the state pension looks like it will be so generous in future. The triple lock thus has the potential to harm self-provision and make pensioners more reliant on the state than they are at present.

At some point a government is going to have to be brave enough and say: sorry, but the triple lock has the potential to destroy the public finances and cannot continue. Unfortunately it is not going to be the present government. Labour has yet to announce a policy for its manifesto. It could strike a blow for fiscal responsibility if announced it was going to ditch the triple lock and increase state pensions by either CPI or average earnings instead.