About 165 million Americans get their health insurance through work, and yet most don't spend much time considering what their employer is offering in the way of benefits and what it will cost.

In fact, employees only spent about 45 minutes a year, on average, deciding which benefit options suit them best, a report from Aon found.

Open enrollment season, which typically runs through early December, is an opportunity to take a closer look at what's at stake.

And, for starters, costs are going way up.

Costs are rising

The cost of health care has been rising steadily for years. More recently, there's been a noticeable jump.

For employers, those cost increases are reaching a post-pandemic high, according to WTW, a consulting firm formerly known as Willis Towers Watson. U.S. employers project their health-care costs will increase by 7.7% in 2025, compared with 6.9% in 2024 and 6.5% in 2023, the firm said.

Because of higher costs, employers are considering new ways to adjust their plan offerings, WTW found.

To that point, 52% of companies said they plan to implement programs that will reduce total costs, and just as many intend to steer to lower-cost providers and sites of care, which may mean a narrower network of doctors from which to choose.

Currently, employers subsidize about 81% of health-care plan costs, on average, while employees pay the remainder, according to professional services firm Aon.

However, some of the higher costs will also inevitably get passed on to employees.

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Roughly one-third, or 34%, of employers expect to shift some of the expense to employees through higher premiums or by raising co-pays on high-deductible health plans in the year ahead, the WTW report found.

The cost per employee is expected to jump 5.8% on average in 2025, marking the third consecutive year of health benefit cost increases above 5%, after a decade of averaging only around 3%, according to a separate report by consulting firm Mercer. 

"These are changes employees will feel," said Beth Umland, Mercer's research director of health and benefits.

For workers, health-care expenses are already high: Family premiums for employer-sponsored health insurance rose 7% this year to an average of $25,572, KFF's 2024 benchmark employer health survey found. Workers are responsible for more than $6,200 of that amount, while employers pick up the rest.

"With cost increases reaching a post-pandemic high, companies are concerned about the burden it's putting on their workforces, especially since it affects decisions about insurance coverage and care," Tim Stawicki, WTW's chief actuary of health and benefits, said in a statement.

Consider your health-care expenses

Often employees are presented with options for medical insurance plan selections: one with a higher monthly cost, known as your premium, and a lower deductible, which is the amount you'll have to shell out before your employer's plan kicks in, and another option with higher out-of-pocket costs but lower premiums.

"Most of the time when you go through open enrollment, the first thing you see is the deductible and out-of-pocket costs," said Regina Ihrke, WTW's health, equity and wellbeing leader for North America.

When weighing options, use previous years as a guide, advised Gary Kushner, chair and president of Kushner & Company, a benefits design and management company.

He said you should consider: "Am I a low-, medium- or high-claims family? Did I have an incident that required acute care or basically lots of preventative care?"

If you usually only go to the doctor, say, once a year for a check-up, you might want to opt for the so-called high-deductible plan with the lower monthly cost. 

Health savings accounts

Along with a high-deductible health insurance plan, more than 50% of employers also offer a health savings account, or HSA, which can help with additional health-care costs.

To be able to use an HSA, you must have an eligible high-deductible health plan. The IRS defines "high-deductible" as at least $1,650 for self-only plans or $3,300 for family coverage for 2025.

The IRS also determines the maximum allowed contribution each year: The new HSA contribution limit for 2025 will be $4,300 for individuals, up from $4,150 in 2024, and $8,550 for families, up from $8,300 in 2024. Employees 55 or older can make an additional $1,000 catch-up contribution over the IRS annual limits.

HSA contributions then grow on a tax-free basis, and the funds can cover out-of-pocket expenses, including doctor visits and prescription drugs, including expensive weight-loss medications.

As costs continue to go up, HSAs are a key safety net for managing these out-of-pocket expenses, WTW's Ihrke said. Any money you don't use can be rolled over year to year.

"Make sure you are considering how to put some money into that savings account so you can use it to pay for a doctor's bill or save it for future years," Ihrke explained.

Life and disability insurance

During open enrollment, employees may also be presented with different disability and life insurance options, which are often included in a standard benefits package.

Employer-issued life insurance policies typically amount to a year's salary. You can buy additional life insurance through your employer. This is called supplemental life insurance, or voluntary life insurance, and it's optional coverage that you can add to your employer's basic group policy.

With disability insurance, there are two basic kinds: Short-term disability generally replaces 60% to 70% of your base salary and premiums are often paid by your employer. Long-term disability, which ordinarily kicks in after three months to six months, typically replaces 40% to 60% of your income.

Even if you have these policies through work, it could be a fraction of what you need to protect young children or other dependents.

Consider what's the right amount for you and your family, then weigh whether you want to buy additional coverage, or supplemental insurance, through your workplace group plan or shop for your own policy, a move many advisors recommend.

Take advantage of voluntary benefits

Additional benefits may be optional but equally important these days, particularly when it comes to well-being. Going into open enrollment, nearly 1 in 5 employees cite deteriorating mental health, according to a recent report by Gallagher.

"More so than ever we are seeing employers looking to address the broadening needs in their workforce," said Tom Kelly, principal in the Gallagher health and benefits practice, and "today's employees are looking for more holistic wellbeing support."

Some wellness initiatives may include financial coaching, stress management classes and even discounts on gym equipment.

There could also be tuition assistance, student loan repayment programs, backup child care and stipends for enrichment programs and camps, which can go a long way toward improving long-term wellbeing.

Although these types of benefits are voluntary, "they are becoming a bigger part of the value proposition," Kelly said.

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