Every year, employers offer a window of time for employees to make changes to their insurance and benefit plans. It's time to be tax smart when making choices.

Though the math may seem complicated, just a few, simple considerations and adjustments can save you big in the long run. We talked with certified public accountant Timothy D. Evans for a few tips on handling open enrollment.

Assess Health Needs

The after-tax cost of health care can be huge, so make sure to move as much of your expenses before the taxman takes his cut. The first consideration is picking the right type of plan.

Opting to be part of a Health Maintenance Organization (HMO) vs.Preferred Provider Organization (PPO) will definitely depend on your immediate health needs.

"Someone who just needs an annual check up and who doesn't get sick a lot can go with an HMO," says Evans. "Getting expensive treatments can be tougher with an HMO but being in an HMO now doesn't mean you can't be in a PPO later."

A PPO is a more expensive option but can be beneficial for families needing more intensive treatments. 

Look into Flexible Spending Accounts

Another way of managing the rising expense of out-of-pocket health care costs and dependent care is to take advantage of flexible spending accounts. Known as FSAs, these accounts allow you to put aside a portion of your salary, free from payroll tax, to use towards qualified expenses. 

Maximize Retirement Benefits  

When it comes to 401k and 403b plans, "the key is to find out what your employer matches and contribute at least that amount," says Evans. Despite recent troubles in the stock market, investing as much as you can afford in your company-sponsored retirement plans is still a great investment strategy. 

Employees should also see if their company offers a Roth 401k plan. These plans, which make after-tax contributions, allow employees to grow their funds tax-free and withdraw funds tax-free at retirement. According to Evans, this would appeal to someone for whom saving on current taxes is less a consideration than saving on future taxes.  

—Timothy D. Evans is a certified public accountant with Vicenti Lloyd & Stutzman LLP in California.