Getting married isn't just about merging hearts and families. It's also about combining your finances. Here's how to get off to a great start.

1. Inform Your Employer

You'll need to submit some paperwork to your employer to ensure that your spouse is covered by your insurance and receives other benefits. Do this:

  • Add your spouse to your health insurance. Health insurers generally permit changes in health coverage outside of their autumn enrollment windows when there's a life event like getting married. For newlyweds, if you both already have coverage through your employers, you can save money on premiums by choosing just one of their health plans. To figure out which one, tally up all your out-of-pocket health expenses for the past year and compare the total with how much you'll pay in premiums, copays, and deductibles under both plans. Choose the plan that will cost you the least unless the other plan offers a better choice of participating doctors, practices, and hospitals.

    Typically, you must do this within 30 days of your marriage, says ReKeithen Miller, a certified financial planner with Palisades Hudson Financial Group in Atlanta. You always can make a change again during the open enrollment period.

  • Change your beneficiaries. You'll need to sign separate forms for employer-sponsored insurance, your 401(k), and other retirement accounts or pensions. While the law automatically grants your spouse your 401(k) if you die, life insurance proceeds go to the beneficiary you choose so you may have to adjust that. If you have insurance plans outside of those offered by your employer, be sure to also consider changing those beneficiaries as well.

  • Adjust your income tax withholding. This is important for newlyweds that don't want an unpleasant surprise when tax time arrives. By combining your incomes, you'll move into a higher tax bracket. If you don't adjust your income tax withholdings now, you could owe a lot more next tax season. Ask your employer for a new Form W-4 or download it.

  • Revisit retirement-account contributions. You'll run into new tax considerations once you're married. If, say, your spouse is self-employed and has been making tax-deferred contributions to an IRA, as a married couple you may not be able to get the full deduction from those contributions once your incomes are combined. The IRS caps how much you can contribute to an IRA if a spouse is covered an employer-sponsored retirement plan like a 401(k) or 403(b); the cap applies even if the spouse doesn't currently contribute to that plan. 

2. Change Your Official Documents

If you change your name when you marry, you'll need to make changes to some documents. Depending on the document, there may be a fee.

  • Social Security card. All newlyweds can keep their old Social Security number, but you'll need to complete a name-change application. You can download the application online but you can't apply for the change online. You'll either have to take it to a local Social Security office, or submit it by mail. To make the change, Social Security requires either your original marriage certificate, or a copy that's been certified by the issuing agency—a town clerk, for instance. You'll also need another proof of your identity, such as a driver's license or passport.

  • Driver's license. You'll need to change your name on your license. To do so, contact your local motor vehicle agency

  • Passport. If you renewed or got your passport less than a year ago, you can make the name change at no charge. You'll need to fill out Form DS-5504. Otherwise, you'll be charged the current fee. The U.S. State Department has detailed instructions.

You can handle all this yourself or you can pay a service to help you complete the forms. One service, MissNowMrs, offers a free trial that gives you access to IRS Form 8822 (Change of Address). To complete more than that, you'll pay a one-time fee of $29.95 or $69.95. (Note: this service's privacy policy says that it uses VeriSign security and that the site doesn't share your information. Even so, we recommend that you do not input your Social Security number.)  

3. Consult a Tax Expert

While it's not romantic, it's wise for newlyweds to meet with a financial adviser or tax professional especially if your combined income is significant. "You need to understand how your entire tax picture is going to change," Miller says.

  • Determine your filing status. Filing taxes jointly usually results in a lower bill than choosing the married-filing-separately status. But that isn't always the case, says Mark Luscombe, principal tax analyst for Wolters Kluwer Tax & Accounting, a Riverwoods, Ill.-based tax and business software publisher. "There's a marriage bonus for filing jointly when the differences in income are great," he says. "But if both spouses work and have roughly equal incomes, there's a marriage penalty—especially if they have high incomes." 

  • Plan for extra tax. At higher income levels, the IRS's tax brackets favor single filers. A single person making $90,000 stays within the 25-percent tax bracket. But a couple each making $90,000—for a total of $180,000—face a marginal tax of 28 percent.

  • Check out new tax breaks. If one of you has significant student debt, getting married and filing jointly may allow you to deduct more interest than if you had remained single. Why? Because the deductibility of student loan interest disappears if you're a single person with a modified adjusted gross income of $80,000 or more. But if you're married, you can deduct interest up to a modified adjusted gross income of $160,000.