Under the German system, residents can generally start receiving a pension if they provide evidence of 35 years of contributions. Those who can show they have contributed for 45 years are able to retire earlier.
But the cost of living crisis and an ageing population have put strain on the system, with one in five pensioners receiving less than 1,200 euros (£1,000) a month from the state, according to a recent German government report.
The situation is said to be even worse in eastern Germany, where around a third of long-term pensioners receive funds below the EU average. In Brandenburg, pensioners who have paid into the system for more than four decades are receiving 1,200 euros per month.
The monthly cost of living in Germany varies between states, but it can be up to 3,000 euros, according to Welcome Hub Germany, a relocation website.
Ms Wagenknecht, who is seeking to turn elderly welfare into a key issue ahead of the federal elections, has called for the government to resolve the situation by adopting the Austrian model.
In Austria the monthly payout to pensioners is generally 800 euros higher than in Germany, according to German newspaper Die Welt.
Ms Wagenknecht said the disparity was “disrespectful to the life achievements of those who have paid in [to their pensions] for decades.”