Now is the time for teachers and nonprofit employees with 403(b) retirement plans to assess their investments.

Right now.

On Sept. 24, new Internal Revenue Service regulations take effect that make it more difficult for employees to shift the assets in their 403(b) accounts from one provider of mutual funds and other investments -- such as Fidelity Investments or Charles Schwab -- to another without suffering a tax penalty.

"If you don't evaluate your financial situation now, you might be locked in until the time you retire or leave your employment," said Don Deans, financial consultant at Capital Investment in Raleigh. "Anyone who is a participant in a 403(b) needs to consult a knowledgeable financial advisor immediately."

WHAT IS A 403(B)? It's a retirement savings plan that allows employees to invest pretax dollars -- just like the corporate world's 401(k), but for employees of schools and nonprofits. Workers nationwide have about $680 billion in 403(b) accounts, compared to nearly $2.7 trillion in 401(k) accounts, according to the Investment Company Institute in Washington, D.C.

The current annual contribution limit for 403(b) plans is $15,500 for most workers, plus an extra $5,000 for those 50 and older with 15 years of service.

WHO OFFERS A 403(B)? School districts across North Carolina, state and public universities, and nonprofit employers such as hospitals.

At the Wake County Public School System, 3,777 out of 14,933 eligible employees participate in a 403(b) plan, said spokesman Chip Sudderth.

WHY CHANGE 403(B) RULES? The goal is to give employers more oversight. The deadline for employers to develop a written plan for administering 403(b)s is Jan. 1, 2009.

HOW WILL ASSET TRANSFERS CHANGE? Under today's rules, many workers can transfer 403(b) money from an employer-sponsored provider to any financial institution that offers 403(b) investment plans -- including insurance companies that sell annuities, mutual fund companies such as Fidelity Investments, and brokers such as Merrill Lynch. This gives another option to employees unhappy with the investment choices offered by their employer.

The new rules will restrict transfers to providers with which an employer has an agreement.

Dan Otter, a former teacher who runs an educational Web site, 403bwise.com, contends many employers don't provide good investment options such as low-cost mutual funds to employees.

ARE ALL 403(B)S AFFECTED? No. A minority of employers already restrict transfers, said Kevin Watt, vice president of business development at Security Benefit, which offers mutual funds and annuities for 403(b) plans.

UNC-Chapel Hill, for example, limits account transfers to providers it has contracts with. As a result, UNC-CH employees won't be affected by the new regulations, said Brian Usischon, director of benefit program administration.

WHAT ELSE SHOULD I KNOW? Some providers assess a surrender charge for shifting funds to a different provider. Any penalty should be factored into deciding if it makes financial sense to move your 403(b) money.

Some providers have set earlier deadlines for accepting fund transfers. Pacific Life Insurance Co., for example, has a Sept. 17 deadline. "It gives us a week to process all of the paperwork," said spokesman Tennyson Oyler.

Even if you're satisfied with your employer's offerings, don't forget 403(b) accounts from past employers. The same Sept. 24 deadline applies to those accounts.

It's an opportune time to consider consolidating multiple 403(b) accounts with a single provider, said David Byrd, a financial consultant at Capital Investment.