The survey of 2,500 workers aged 45 and over found total savings in the Midlands and the North are on average less than £98,000.
For a moderate standard of living in retirement the Pension and Lifetime Savings Association (PLSA) estimates £248,000 is needed.
Steven Cameron, pensions director at life insurance company Aegon, said the pensions gap could be due to the sectors that are more prevalent in different areas of the country.
Speaking to HR magazine, he said: "Pensions adequacy is largely driven by the age people begin saving, which is often dependent on how much you earn.
“It can also vary by industry sector, with employers in some sectors tending to offer more generous pension benefits than others to attract and retain employees.
“Average earnings, the mix of industry sectors and employment opportunities vary across the country.”
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Areas of the country with a higher proportion of public sector workers, Cameron added, are likely to have more savings due to pensions being more generous than in the private sector.
A quarter (25%) of workers surveyed said they definitely will not have enough money to live on when they retire, while 36% worry they will need to dip into their savings before retirement.
This figure rose for those living in Greater London (45%) and the West Midlands (42%).
Lily Megson, policy director at financial planning company My Pension Expert, said Londoners’ pensions are impacted by the higher cost of living in London.
Speaking to HR magazine, she said: “The retirement gap between different locations can be attributed to the significant variations in average salaries and the cost of living, most notably things like rents and house prices.
“Locations with a higher cost of living, such as London, may require individuals to allocate a larger portion of their income towards essential expenses instead of their pension pot, or even feel the need to access their savings before retirement.”
The study also found 60% in the North East, Greater London and Wales worry they will need to work past the state pension age (66), compared with 52% of those in the North West and Yorkshire and Humberside.
Nigel Peaple, director of policy and advocacy at the PLSA, said employers can help matching pension contribution levels.
Speaking to HR magazine, he said: “There is already consensus that the minimum automatic enrolment contributions are currently too low, and an evolution is needed.
“Organisations can support this process by offering to match contribution levels.
“For savers to reach an adequate income in retirement contributions should rise slowly from 8% to 12% over the next decade and should be a 50/50 split between the employer and the employee.”
Separate research from Phoenix Insights found over one in seven (15%) did not know where their main source of income will come from when they retire, rising to one in five (19%) of those in the East Midlands.
Megson said more education should be available to employees to help them make informed pension choices.
She said: “Preparing for retirement is not just a question of having sufficient earnings to build up a healthy pension pot. Education and advice are absolutely essential.
“It is crucial that people understand how pensions work and the options that are available to them as they develop savings and investment strategies for retirement.
“This may include organising workshops, seminars, or online resources that cover topics such as retirement planning, investment diversification, and maximising employer-sponsored retirement plans.”
Cameron also emphasised the importance of understanding pensions from a young age.
Research from NOW:Pensions last month (June) found most young people aged 11 to 27 (86%) support the UK government’s proposal to reduce the age of automatic enrolment from 22 to 18.
Cameron added: "While there’s no magic solution for either employers or individuals, it’s really important for individuals to engage with their pension savings as early as possible and to find out whether or not they are on track for the standard of living they want in retirement.
“The earlier this is looked at the greater the chance the individual can get back on track.”