Less than a third of people over 50 are economically active in Birmingham, according to BBC-commissioned research.
The figure of 32.8% was lower than the Black Country area percentage of 37.5%.
Economically active means anyone who does anything which puts money into the economy and this mainly refers to working, but it could be selling shares, or spending savings.
The study carried out by Experian looked at how areas would be affected by an increasing ageing population.
A spokesman for Birmingham Chamber of Commerce said: "We know Birmingham has the highest proportion of unemployment among the core cities in the UK.
"There's bound to be a high proportion of people who rely on their partners for economic support.
"You can't expect people on low incomes to spend money if they haven't got it."
Mike Dell, Black Country Chamber of Commerce president, said there were relatively high levels of unemployment in the area, which has affected all age groups.
He added: "In the very early stages of the recession it's affected white collar workers more, salaried office-based employees.
"We found it was places like Halesowen, Stourbridge, Kingswinford [which] were the worst affected.
"There's been a lot of effort with all kinds of schemes encouraging [firms] to take on school leavers and younger people."