MPs demanded the coalition link pension increases to RPI inflation again today after one man's online petition was signed 110,000 times.
Civil servant Jim Singer of Aberdeen started the petition to try to stop the switch from RPI to the usually lower CPI rate.
It stated the change to CPI would "mean a steady reduction in spending power for pensioners as they progress into their retirement," reducing the total value of pensions by up to 25 per cent.
Petitions on the government's websites need at least 100,000 signatures to be considered for paliamentary debate.
Mr Singer said: "I'm delighted that we've finally secured the debate. I was particularly annoyed by this change because I've worked for the government for 35 years and for all that time I was guaranteed a pension that would rise by RPI.
"This switch will make me and many workers in the private and public sectors thousands of pounds worse off."
Mr Singer and his wife Sheena, who was in the pension scheme at British Telecom, said they stand to lose £31,000 between them if they live for 20 years after retirement because of the switch from RPI to CPI.
The change was implemented by Chancellor George Osborne in his June 2010 Budget.
More than two million public-sector workers went on strike on November 30 last year against the decision, as well as the proposals to increase the retirement age.
During the parliamentary debate, John McDonnell MP proposed a motion to reintroduce the RPI calculation, stating that the speed in which the petition attracted over 100,000 signatures suggested the strength of concern.
He said: "Unfortunately there are many other Jim Singers that this government is penalising by getting them to pay for the deficit with their pensions."
PCS general secretary Mark Serwotka added: "Jim did a magnificent job to launch this petition and send out hundreds of personal emails to urge people to sign it."