Rachel Reeves has been warned that workers may feel the effects of an above-inflation increase to the state pension, in accordance with the triple lock. Pension specialists at Spencer Churchill Claims Advice said that, even though the rise is welcome, it raises “serious questions about long-term affordability and the likely impact on workers”. People on the full new state pension will receive more than £550 a year extra, with those on the full basic state pension receiving around £440.

A spokesperson for the claims firm said: “This increase of up to £550 a year will be very welcome for millions of pensioners who are finding it increasingly difficult to keep up with rising living costs. However, the policy is becoming significantly more expensive for the Government every year. The triple lock now costs far more than originally forecast which increases the strain on an already tight Budget.”

The OBR wrote in its fiscal outlook yesterday that the triple lock will be offset between 2026 and 2028 by the rise in the state pension age from 66 to 67.

The watchdog’s forecast for pensioner spending, which includes pensioner housing benefit, pension credit, winter fuel payment, and state pension expenditure, is £161.2billion for 2025-26 and £195.4billion for 2030-31.

The spokesperson added: “Analysis from the Office for Budget Responsibility has highlighted that the triple lock is now costing around three times more than expected when it was introduced. Pensioners will benefit immediately but the wider question is how these increases will be funded in the long term without shifting the financial burden onto working households.”

Speaking before the Chancellor’s speech yesterday, they warned that, if she announced a restriction of salary sacrifice pension arrangements and an extension of the freeze of income tax thresholds, workers “could find themselves paying more”.

The specialist added: “There is a delicate balance between giving pensioners stability and protecting the retirement prospects of those who are still saving.”

The chief executive of the Resolution Foundation think tank Ruth Curtice told BBC Radio 4’s Today programme this morning that while spending on pensioner and health and disability benefits are rising more than expected, “we didn’t hear much yesterday of how they might take action in the future”.

In September, the Conservative Shadow Chancellor, Mel Stride, admitted the triple lock is “not sustainable” in the long term.

He added: “But of course, what I’m dealing with is now and where we stand at the moment, is we remain committed to the triple lock.

“And that’s the path that we will be taking.

“But as to the future, and after future general elections, and so on and so forth, who knows.

“But that’s the position we’re in at present.”