That great salary offer might not be as valuable as you think

Next time you're assessing a job offer, don't focus solely on salary. The value of benefits that are (or aren't) on offer could make a big difference to your bottom line.

Wide variations in benefits mean that two workers earning the same pay may have very different levels of total compensation, according to a new report from The Pew Charitable Trusts. The higher a worker's pay, the more valuable the benefits received — and the wider the potential gap.

Someone earning roughly $15 per hour, for example, receives benefits worth another $6.10 per hour. The report found a quarter of those workers received less than $4 in added benefits, however, while another quarter received more than $8.

"Differences in financial security could really be stark," said Sarah Sattelmeyer, an officer on The Pew Charitable Trusts' financial security and mobility team, in a press briefing Wednesday.

Employees looking to switch companies won't necessarily do better: Much of that gap stems from certain industries being more likely to offer valuable benefits than others. Utilities and mining companies are among the biggest spenders, Pew found, while food service and retail trade employers are among those that spend the least.

Nor does working for an employer in the upper end of the range necessarily improve workers' financial health, Sattelmeyer said. The real value of benefits is in the details. A company might pay a lot for a health insurance plan that still has high out-of-pocket costs, for example, or offer a benefit that isn't useful for you in particular (say, tuition reimbursement or adoption aid).

Still, it's worth factoring in benefits when you're comparing job offers. The value of retirement income, health care and other benefits are worth an average 17 percent of employer pay, with paid time off worth another 11 percent, according to Aon Hewitt's Benefit Index.

"Pay level is a big factor in the result," said Mark Friedman, a partner in Aon Hewitt's retirement and investment practice. "An employee looking for employment at a retailer with a low starting salary could find health-care benefits alone have a value well over 20 percent of pay."

Insurance and retirement represent some of the most valuable potential perk areas, so start your digging there, said Carolyn McClanahan, a certified financial planner in Jacksonville, Florida.

On the retirement plan front, figure out how much you might gain from the employee match and look into any extra profit-sharing on offer, said McClanahan. Ask for details on plan vesting, as well as investment options and fees, which can make a big difference in your savings balance over the course of your career.

For health insurance, compare out-of-pocket costs, including the deductible and premiums, against what you'd pay on the open market, she said. Make sure you can actually benefit from the coverage, too.

"Is it a health plan that's widely accepted by the doctors you go to?" said McClanahan. "Or is it a tight network?"

Other insurance benefits like group life insurance and short-term disability tend to be more valuable for consumers who aren't in great health — and so would pay higher rates on their own, said McClanahan.

Keep in mind that some benefits, like vacation time, may be negotiable.

"If you're in a job where labor supply is tight, be bold about asking for things that matter," she said.

Current employees should also scour work perks on offer to make sure they're not leaving money on the table in the form of discounts, incentives and financial wellness initiatives .

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