(Bloomberg)--Employers are squeezing their workers retirement savings, holding back on both the amount and the timing of 401(k) matching funds and dragging out vesting schedules. Taken together, these measures are making it more difficult to save for old age.

Major companies that have engaged in such practices in recent years include Whole Foods Market Inc., Facebook Inc., Oracle Corp., Caesars Entertainment Corp. and JPMorgan Chase & Co.

The most frugal have been scaling back company matches and setting lower limits for the maximum annual payment theyll make to a 401(k) account, according to hundreds of government filings analyzed by Bloomberg. A difference of three percentage points on a match can add up to hundreds of thousands of dollars lost for employees over the course of their careers.

Theres been an implicit contract for years and years -- workers save and companies match -- but now theyre changing the rules, said Brigitte Madrian, a Harvard Kennedy School professor who studies retirement policy and corporate management. Most individuals cant do it on their own. Were going in the wrong direction.

Companies including International Business Machines Corp. and Hewlett-Packard Co. say their 401(k) policies are partially dictated by bottom-line considerations and marketplace competition. Others say that when setting their 401(k) contributions, they consider a wide range of benefits and their costs as well as employee preferences, including health care, vacation policy and incentives such as performance bonuses, stock options and outright grants.

CHOOSING BENEFITS

In addition to our 401(k) plan, we offer benefits that our more than 80,000 Team Members have the opportunity to actually vote on, including paying only $0-$15 per paycheck for health insurance premiums, robust store discounts, and paid time off that carries over, Mark Ehrnstein, global vice president of Team Member Services at Whole Foods, said in an e-mail. We offer other benefits such as a broad-based stock plan that awards 95% of options to non-executives, and we have a gain-sharing program that rewards teams for labor productivity.

The advent of 401(k) retirement savings since the late 1970s was supposed to help secure and boost the retirement savings of baby boomers. The plans, originally conceived as a supplement to pensions, have since mostly replaced them. Workers can direct up to $17,500 of pretax income toward their 401(k)s this year and an additional $5,500 for those aged 50 and older.

CONTROL, PORTABILITY

The investment industry has said for the past 30 years that 401(k)s are a big improvement over pensions, giving employees more investment choice, more control over retirement planning and more portability amid the frequent job changes of the modern workforce. That, at least, was the promise held out by the industry that now holds $4 trillion in retirement assets.

It hasnt worked out that way. The median balance in 401(k) and individual retirement accounts for households headed by people ages 55 to 64 who had accounts at work was just $120,000 in 2010, according to the Center for Retirement Research at Boston College.

Those savings will provide only $4,800 a year, assuming seniors withdraw 4% annually, the amount recommended by retirement benefits experts to ensure retirees dont run out of money in their lifetimes. Financial planners say that retirees need savings of at least 10 times their annual income to live comfortably.

COST SAVINGS

Companies that adopted 401(k) plans have realized they can adjust them, tinkering with the plumbing and, in the process, costing workers millions in retirement savings. Whats more, contributions arent mandatory as they generally are in traditional pensions. Since 401(k) contributions are measured as a percentage of payroll, the savings from any cuts are realized immediately. Some employers are changing what they offer to lower their own expenses and improve profits.

Thats what AOL Inc. tried last week when Chief Executive Officer Tim Armstrong announced the company would make 401(k) payments in one lump sum after the end of the year. When he blamed the change on spiraling health-care costs, including $2 million spent on care for distressed babies and the higher cost of benefits under President Barack Obamas Affordable Care Act, employees cried foul. Within days, Armstrong apologized and AOL reversed its decision.

DELAYED CONTRIBUTIONS

The tiff at AOL provides a window into a growing practice among companies of quietly scaling back retirement contributions, according to documents reviewed by Bloomberg. Many companies, including some major U.S. banks that sell investments to retirement plans, now delay their contributions to their employees 401(k)s until early the following year, paid in one lump sum rather than through regular payroll checks. Those changes depress employees compounded returns. And employees at some companies who change jobs before the end of the year wind up leaving company matches on the table.

Its starting to feel like déjà vu at the start of the Great Recession, said Marcia Wagner, president of the Wagner Law Group, who specializes in employee benefits. Right now employers are looking at cost savings and they are definitely looking at their 401(k) plans.

The corporate cutbacks are adding to employees financial anxieties at a time when incomes are stagnant and even those earning low-six-figure incomes arent accumulating enough retirement savings. A generation since the shift from company- funded pensions to mostly employee-funded 401(k) accounts, half of baby boomers aged 50 to 64 dont think theyll ever have enough to retire, according to a 2011 survey by the AARP.

WIDE VARIATIONS

The details of retirement plans vary widely from company to company. A typical match is 3% of pay and requires the employee to contribute 6% to get that company money.

Facebook offered no company match in 2012 and 2013. Whole Foods provides an annual match of $152 based on a formula of 15.2% on the first $1,000 that workers contribute. That compares to more generous companies, such as the biotechnology company Amgen Inc., which contributes 5% of workers salaries whether they contribute or not. The company also will match as much as another 5% of employee salary deferrals.

Facebook says it will decide each year at its discretion whether to make a contribution. The company plans to provide a match later this year as part of a comprehensive set of benefits, said Facebook spokesman Tucker Bounds.

Whole Foods Ehrnstein said his companys match was approved by 84% of its 80,000 employees.

FULL MATCH

Kroger Co., the grocery store chain, is more generous than many companies. It matches 100% of the first 3% of workers salary deferrals, plus 50% of the next 2% of workers compensation. The company generally also pays an additional contribution of 1% to 2% based on tenure.

Krogers 401(k) match program is a way to attract and retain employees and is a reflection of our company values, said spokesman Keith Dailey.

Most employees have no idea how their companys plan stacks up against competitors because the details are buried in opaque government filings. While companies file reports annually to the Labor Department that are available online, theyre difficult to access and the information provided isnt consistent.

Corporate tinkering with 401(k) plans accelerated in the wake of the 2008 financial crisis. About 18% of 334 companies surveyed by consultant Towers Watson suspended or reduced contributions, a response to an urgent need to conserve cash. Yet when the liquidity crisis subsequently eased, about 23% of companies that reinstated company matches offered less generous contributions than before the recession.

LOWER MATCH

Caesars Entertainment, the casino resorts and online gaming company, suspended its 401(k) match in 2009, when it was 50% of employee contributions up to 6% of pay, not exceeding the federal cap. When the company reinstated the match three months into 2012, the maximum contribution was $450 for that year, and it was $600 for all of 2013. Gary Thompson, a company spokesman, declined to comment on the change.

Hewlett-Packard lowered its match during the financial crisis from 6% to 4%, where it has stayed.

The change was made to align with comparative companies, said HP spokesman Michael Thacker.

HUGE DIFFERENCE

A few percentage points up or down can make a huge difference come retirement day. A 25-year-old worker with a starting salary of $25,000 whose employer matched 3% would see his or her 401(k) balance reach about $624,000 if he or she saved consistently until age 65 and got 6% annual returns, according to calculations by Jack VanDerhei, research director at the Employee Benefit Research Institute.

All things being equal, that person would have about $812,000 -- or 30% more -- if his or her company matched 6%. The analysis assumes an annual wage growth of 3% so the workers ending salary at age 65 is $81,550.

Top executives with high compensation likely dont care what their company contributes to a 401(k), but for employees in the ranks it can mean the difference between financial security and scarcity in old age, said Mike Alfred, CEO of BrightScope, a San Diego firm that ranks retirement plans.

Some companies, especially small businesses, offer no match at all. The number of 401(k) plans that contribute declined 3% in 2012, according to a survey of government filings of more than 400,000 plans by American Investment Planners, a financial adviser in Jericho, New York.

VESTING PERIODS

Companies also save costs through lengthy vesting requirements, forcing employees who leave to forfeit unvested contributions. Employees at Oracle, for instance, are 25% vested after one year of employment, another 25% after a second year and only fully vested after four years. In 2012, Oracle used $3 million in nonvested payments to offset its matching contribution obligations, according to government filings. An Oracle spokeswoman, Deborah Hellinger, declined to comment.

Another form of skimping occurs when companies delay 401(k) matches until the end of the year or early the following year. IBM shifted last year to a lump-sum payment. Workers who left the company before Dec. 15 didnt get their match for the year.

Younger workers who tend to be more mobile are really going to get hammered by this, Harvards Madrian said of delayed matches and long vesting schedules. While the amounts left on the table may only total a few thousand dollars, over the course of decades of compounding and investing, they have the potential to significantly enhance retirement portfolios, Madrian said.

FINANCIAL GIANTS

Many large financial institutions also delay matches. Among these are Citigroup Inc., Goldman Sachs Group Inc. and Morgan Stanley. Citigroup and Goldman in e-mails said employees who leave during the year get the portion of the match owed. Morgan Stanleys spokesman Matt Burkhard declined to comment.

JPMorgan Chase, the largest U.S. bank, began delaying matching contribution payouts in 2009. The company, which sells investments to retirement plans, urges savers to Invest early and often, in a J.P. Morgan Asset Management website.

The bank waited until January 2014 to match retirement deferrals its own workers made last year. The bank employed about 7,500 fewer people at the end of December than a year earlier, according to its fourth-quarter earnings filing. Employees who left the bank because their positions were eliminated got their matching contributions even if they werent employed on Dec. 31; JPMorgan declined to comment on the exact number, according to spokeswoman Jennifer Kim.

Meanwhile, the bank gave 6% of salary up to $600 to U.S. employees 401(k)s if they earned less than $60,000 a year. The award was made to employees with at least one year of service at the end of 2013. The program has been in place for at least two years and the bank hopes to continue it, Kim said.

Its ironic that the very financial companies that earn fees by sponsoring 401(k)s are themselves cutting back on contributions for their employees, said Teresa Ghilarducci, an economist at the New School. Even as they tell people to save more.

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