The Ides of March have come and gone, the spring bulbs have started to bloom, and almost a quarter of the year has already gone by. And while you'd probably rather be indulging your spring fever by puttering in the garden or tracking baseball's spring training, it's also a good time to take a close look at your 401(k).

A quarterly check on your finances is never a bad idea, and spring may be the ideal time to look at your workplace retirement accounts. After all, you often pay close attention to your taxable accounts at the end of the year, when tax planning is on your mind. You also nurture your IRA when it comes time to invest your annual contributions.

That may leave your 401(k) feeling a little neglected. After all, these workhorse accounts operate mostly on autopilot, as they silently fill your retirement coffers paycheck after paycheck. Take a few minutes on a rainy spring day to look over yours.

Contributions. If you've been hoping to nudge up your 401(k) contributions a little bit, why not start now? After paying off your holiday bills, you may have a little more breathing room left in your paycheck. It's also too soon for your summer vacation to sabotage your perfectly planned budget. So think about knocking 1% more of your salary into your deferred-contribution account. If you're not contributing enough to get your company's full matching contribution, definitely put the 1% plan on your spring to-do list.

It doesn't sound like much, but adding just 1% of your salary makes the change painless enough to stick and can become quite profitable over the long run. Repeat this habit once a quarter all year long, and you'll be thanking yourself in retirement. Even though you'll be socking an extra 4% of your salary away by year's end, you probably won't even notice that it's missing from your paycheck.

Investments. While you're looking at your 401(k), review your investment choices. If you've had some losing investments, you might not have noticed them before. Now's the time to look.

The Fool's mutual-fund guru, Shannon Zimmerman, recommends index funds as your best IRA investment. They can be a 401(k)'s best friend, too. Why? Because index funds routinely trump most of the managed mutual funds available in the marketplace. If you want to really delve deeply into the world of mutual funds, take a free spin through the Fool's Champion Funds newsletter.

In the meantime, you'll probably be stuck investing in something that your plan makes available. That means it's time to find out whether you have a Foolish 401(k). Take a close look, particularly, at the fees you're paying. Compare your funds' performance with the appropriate index fund. Make some changes if they're needed. It's worth your time to peruse the other funds your plan offers -- chances are good that they've changed since the last time you looked.

Rebalancing. If you're a young worker bee, you may be stuffing all of your savings into stocks with nary a care in the world. Some people may prefer splitting their contributions between stocks and bonds. Whatever your plan, now's the time to make sure that plan is still in place.

Over time, the value of your investments will move out of balance and change your overall asset allocation from what you'd originally intended. Now's a good time to shift them back by rebalancing your portfolio to make sure you're back in line with your desired allocation. If it's been a while since you've thought about it, you might also want to make sure your asset allocation still matches your goals.

After all this scrutiny, you may decide you're really not so fond of your 401(k) investment options at all, and you'd rather put your money elsewhere. If so, check out another great way to save for retirement -- the IRA and Roth IRA. You still have time to maximize the $4,000 contribution allowed for 2006 before you turn your attention to 2007. You'll just need to get your check in by April 17.

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For more Foolish advice on managing your retirement savings, try out our Rule Your Retirement newsletter. Each month, retirement expert Robert Brokamp and his team of writers bring you everything you need to know to retire successfully. See for yourself with no obligation with a 30-day trial.

Fool contributor Mary Dalrymple welcomes your feedback. The Motley Fool has a disclosure policy.