Changing jobs can bring new opportunities—but also new challenges for keeping your financial plan on track.

Starting a job is the perfect time to make sure you're having the right amount for Uncle Sam withheld from your paycheck. Too much, and you're basically giving the government an interest-free loan all year. Too little, and you run the risk of running into some unpleasant surprises at tax time. So whether you do it yourself or consult a tax professional, take the time to estimate your federal and state income-tax liabilities before you start that new job.

If your new employer offers direct deposit, get it. It’s not only convenient, it’s also a great way to manage your money. All the money is automatically deposited into your account on payday, which means you can access it right away without the hassle of waiting days for it to clear. And if you want to get the most out of your money, put it to work. That means finding an interest-bearing checking account.

While settling into your new job, listen closely when human resources mentions the company’s 401(k) plan. You'll want to enroll yourself in the plan as soon as possible. A 401(k) will allow you to start accumulating the retirement savings you need later and tax breaks you want now. This is because your contributions are taken out of your paycheck before taxes, which means you end up paying less in income tax. And the money you put aside in your 401(k) grows tax-deferred until you take it out. Also, if your employer offers a matching contribution, make sure you are contributing up to at least the match; you're basically taking advantage of "free money" from your employer. Why give that up? Another great thing about 401(k) plans is that your assets are portable. When you change jobs you can leave them where they are, take them with you to your new employer or roll them over into an IRA. To make the most of your retirement savings, consider your options carefully and use our chart to help you decide what’s right for you.

• Update contact information. Make sure your bank, insurance company, children’s school and anyone else have your new employer information.
• Change of address. If you moved for your new job,notify your former employer and any financial service providers of your new address. Fill out a change of address form at the local post office, too.
• Keep a record. Save documents related to your separation from your last employer.
• Hold onto your benefits. Find out if you’re entitled to take any benefits with you from your last job. Look over what benefits COBRA provides. Find out about expiration dates of health and life insurance benefits as well as any vested stock options, if you have them.
• Look over your insurance options. Consider carefully whether it’s better to join your new employer’s health care plan or your spouse’s plan. Review the basic disability and life insurance amounts offered by your new employer.
• Update your résumé. Odds are, you may want to look for another job one day.