Identification

The Internal Revenue Service does not directly offer tax incentives for spouses, but couples can lower their tax burden by marrying and filing a joint return. For example, the tax bracket limits for joint returns are twice that of those for a single pay -- except for the top tax brackets -- so a married couple pays fewer taxes when one spouse earns far more than the other spouse, because the spouse with little income drags income from the higher earning spouse into a lower income bracket.

Marriage Penalty

Sometimes a married couple who files jointly does face a penalty, usually because joint income makes them ineligible for a deduction or credit. For example, the earned income tax credit mainly goes to low income families, especially for families below the poverty. Two people that make $15,000, who would normally qualify for the EITC in 2011, would qualify for a much lower EITC because of their combined income.

Important Deductions

Workers sometimes have to pay taxes on health coverage, especially if a domestic receives coverage, but the IRS does not tax health care coverage for both spouses. The IRS taxes inheritances with a value over a certain amount -- $1 million in 2010 -- but a spouse that dies can leave all of his assets to the surviving spouse tax-free. The IRS offers a exclusion of $250,000 on the capital gain of a home sale for a private individual, but $500,000 for a married couple.

Tip

Married couples should calculate their taxes under the status of joint and married, but filing separately. Filing separately may lower a tax bill. For example, if one spouse has large medical bills, it may lower the couple's tax bill file separately if one spouse has a low income, because the IRS only allows taxpayers to deduct medical expenses when expenses exceed 7.5 percent of adjusted gross income, according to Sandra Block of "USA Today."