Jeremy Hunt has committed to keeping the triple lock system to decide rises in the state pension if the Conservatives win the next election.
The chancellor confirmed the policy pledge, which means the increase in the state pension is the highest of average earnings, inflation or 2.5%.
Mr Hunt told the BBC he was confident the "expensive" promise would be paid for by his plans to grow the economy.
Under the triple lock, the state pension is to rise by 8.5% in April.
Labour's Anneliese Dodds did not commit to the policy when asked to respond on the BBC's Sunday with Laura Kuenssberg show.
"We will set out those plans for our manifesto in detail," she said.
Mr Hunt confirmed the current triple lock system to decide how much the payments rise each year would "absolutely" remain if the Conservatives win the general election, which must be held by 28 January 2025.
"When we came to office if 2010, pensioners were more likely to be in poverty than other income groups, now because of the triple lock that we introduced they are less likely to be in poverty," he told the BBC.
"I think that is a very important social change because unlike adults of working age, pensioners can't work, they have retired and so we need to respect that."
Mr Hunt said he realised continuing the policy would be an "expensive commitment", but added: "You can only make that commitment if you're confident that you're going to deliver the economic growth that is going to pay for it."
In response to Mr Hunt's confirmation, Liberal Democrat Treasury spokesperson Sarah Olney said the pledge was a "shameless election trick by the Conservatives" and claimed Mr Hunt was "yet again taking pensioners for granted".
The state pension is a payment made every four weeks by the government to people who have reached the qualifying age and have paid enough National Insurance contributions. More than 12 million people in the UK receive it.
Currently, the pension is worth £203.85 a week for the full, new flat-rate (for those who reached state pension age after April 2016), and £156.20 a week for the full, old basic state pension (for those who reached state pension age before April 2016).
In April, the two payments will rise to £221.20 and £169.50 per week respectively, taking the annual totals to £11,502 and £8,814.
Next month's increase is set to be the second significant rise in the state pension in two years, after a 10.1% increase in April 2023.
The triple lock is designed to ensure pensioners, especially if they rely solely on the state pension, are able to afford rising prices, or keep pace with the increases in the working population's wages.
The rate of price rises in the UK – inflation – has been high in recent years, putting pensioners, as well as working families under financial pressure.
Inflation has fallen sharply from a 40-year high and figures last week showed the rate was3.4% in February – the lowest level in almost two-and-a-half years.
But interest rates are still at a 16-year high after being raised by the Bank of England in recent times to try to slow the pace of consumer prices rising.
It has made borrowing money on things such as credit cards and mortgages much more expensive for households, but has boosted returns for savers.