Alex the Lion, voiced by Ben Stiller in a scene from Madagascar 3: Europe’s Most Wanted. Photo: AP

Call the cops — your pocket’s been picked.

American workers are being ripped off by excessive retirement plan fees — which may force them to work longer or live less comfortably in their golden years, according to a recent study.

For the average US household, the high fees drain about $155,000 from their 401(k) accounts over their lifetimes, the study found.

In one example highlighted in the study, a two-wage-earner household with a median income for their age group contributed an average of 7 percent a year to their 401(k) plan over 40 years.

They earned an average annual return of 8.5 percent. Because of fees of some 2 percent a year on their 401(k) plan, they ended up with a balance of only $354,000 — $150,000 less than they would have had but for the fees.

“That $150,000 or so could have made a tremendous difference in the lifestyle of the couple,” said Robert Hiltonsmith, a policy analyst at Demos, which published the study.

Higher-earning households can pay as much as $278,000 in fees, Hiltonsmith found.

Hiltonsmith compares the typical nest egg to one that carried lower fees — say of roughly 0.40 percent.

High fees, he said, can be just as costly to a worker as market gyrations.

Higher fees and the income they rob from workers is even a greater peril when you consider that the average 401(k) balance for a head of household between ages 35 and 44 is just $36,000.

Those on the verge of retirement, ages 55 to 64, have average balances of only $98,000.

Those balances are low and aren’t growing fast enough to fund a comfortable retirement, the report says.

The “lost decade” of the first 10 years of the century, in which the stock market was basically unchanged, combined with fund managers raising fees to keep profit margins on the lower returns and lower balances, have huge consequences for average Americans saving for retirement.

Millions of Americans, both old and middle-age, are heading for retirement with too little, according to the report.

“Early boomers, or those retiring in the next 10 years, can expect in their retirements to subsist on 77 percent, on average, of what they earned during their peak working years; their children, the Generation Xers, in contrast, will need to survive on 65 percent of their peak earnings years,” according to Hiltonsmith.

If the employer had selected a low-cost 401(k) provider, such as a Vanguard or TIAA-CREF, he says, the hypothetical couple would have made out measurably better.

How can one find out about a plan’s expenses?

You can find your plan’s expenses in the 401(k) plan summary document, which is online, Hiltonsmith says.

“Look at the individual funds you may be using in the plan. And, in general, you should choose the lowest-expense funds,” he says.

Longer term, Hiltonsmith and others are advocating that the entire 401(k) system be overhauled.

“We need something new right now,” he says.

Hiltonsmith advocates a system in which workers are guaranteed a minimum of at least 3 percent growth a year in their retirement savings — a product he calls Guaranteed Retirement Accounts (GRAs).