Photo: Flickr user Michael Theis.

If you've changed jobs recently, or simply have your retirement assets spread across too many accounts, you may be tempted to roll over your 401(k) or IRA assets into a new account. Before you do this, however, there are a few things to consider, as three of our contributing writers discuss below.

Dan Caplinger: One of the biggest mistakes that some people make with an IRA rollover is thinking that they can use it as an opportunity to get temporary access to their cash. It's true that the rollover rules give you up to 60 days between the time that you take money out of your retirement account and the time you redeposit it back into an IRA. As long as you get that done in time, then the rollover doesn't have any consequences, and you were able to put the money to whatever use you wanted during that 60-day period.

Yet there are many potential pitfalls. First, your financial institution will typically withhold tax from a rollover distribution, so you'll have to come up with that shortfall by the time you redeposit the rolled-over money into an IRA, and you won't get reimbursed for it until you file your tax return for the year. In addition, the consequences for missing the deadline can be huge: the amount rolled over will be treated as a taxable distribution, and you'll potentially have to pay penalties as well. Worst of all, you won't be able to get that money back into a tax-favored retirement account, and that could cost you even more in lost tax-deferred returns. Often, your best course is to use a direct transfer rather than succumbing to the temptation of handling your retirement cash, even temporarily.

Jason Hall: Recently a friend asked for some advice on her rollover. She's worked with a financial advisor for years and has been relatively satisfied. I encouraged her to explore her options and take the time to understand how much she was paying, both for his services and for the funds she was invested in.

Long story short: After a recent job change, her advisor was pushing her to roll the funds to him. She decided to do some digging, and it turns out that over the past seven years she's been working with him, the funds her advisor recommended she invest in were all high-fee, low-performance.

I'm not talking about 2% or 3% fees here, but only 1.5% or so on average. But those high-fee funds consistently underperformed the market over the past few years, costing her tens of thousands of dollars in returns. She decided it was time to move on, and now her retirement funds are all invested in low-cost index funds.

Her 401(k) from her former employer would have doubled the assets that were underperforming. By retirement age, my friend would have had potentially hundreds of thousands less, based on bad, expensive advice.

Financial advisors don't work for free. Know how they get paid. Know how much you'll pay (expense ratio) for the funds they recommend. And know how well the funds have performed historically.

Matt Frankel: I'd like to add on a bit to Jason's discussion about fees. An IRA is the way to go if you want to buy individual stocks, but it can be a mistake to roll over your 401(k) into an IRA if you plan on investing in mutual funds.

401(k) plans have access to "institutional" shares of mutual funds, which tend to have lower fees than their retail counterparts. For example, the PIMCO Total Return Fund is one of the most widely held funds by 401(k) plans. The institutional shares (PTTRX) have a low expense ratio of just 0.46%, while the Class A (PTTAX) and Class C (PTTCX) shares, which are available to retail investors, have expense ratios of 0.85% and 1.60%, respectively.

Now, this may not sound like much of a big deal, but it can rob you of thousands of dollars in long-term performance. Let's say that your funds produce 9% annual returns before expenses, and that your 401(k) funds have an average expense ratio of 0.5%. With this performance, a $25,000 investment could grow to more than $266,000 over a 30-year period. If the money is transferred to a retail fund with a 1% expense ratio, the growth is limited to $232,000. That's still a pretty solid return, but moving to a higher-fee fund would be a $24,000 mistake in this case.

All 401(k)s are different, so this isn't a set-in-stone rule. In fact, many 401(k) plans that I've seen have funds with expensive fund options. Just make sure to compare the fees before you decide to get out of your 401(k).