People who paid years of national insurance contributions but don’t live until or long after retirement age unfairly miss out on income under the current system, blasted the pension expert.
In contrast Britons who live longer and can work until they are older receive more income and more flexibility.
Under the current system, anyone can defer taking the state pension in exchange for higher income later.
Yet this is a more difficult option for people who are in manual or physically demanding jobs are less likely to be able to keep working.
The state pension takes no account of differences in occupations, life expectancy or social classes, said Ms Altmann, who served under David Cameron between 2015 and 2016.
Writing in City AM, the former minister said: “National Insurance amounts to a significant percentage of salary for most people, but anyone who does not live to the starting age for state pension will get nothing from this.
“Those who live longer, in contrast, will receive more from the state.”
She added: “At the moment, the state pension is only flexible for those who are healthy and wealthy enough not to need to take it at state pension age.
“If you can afford to wait longer, you can get a higher state pension, but if you cannot manage until that age, it is just too bad.”
Ms Altmann said the flat pension age should be scrapped and instead based on individual circumstances to make the system fairer.
She said: “In general, we need to move away from the idea of just one ‘magic’ age at which people should aim to stop working and live on a state pension.
“This would be fairer to the more disadvantaged and allow them a choice they are currently denied.
“A more flexible system would perhaps allow people to take their state pension at a lower age, either because they are seriously ill or because they have worked for more than 50 years already.”
The comments come after the Government yesterday announced plans to push back retirement for millions of people in their late thirties and forties.
Under the proposals, anyone born since 1970 will now not be able to access their state pension until they are 68.