A filing status for married couples that have wed before the end of the tax year. When filing under the married filing jointly status, couples can record their respective incomes, exemptions and deductions on the same tax return. Married filing jointly is best if only one spouse has a significant income. However, if both spouses work and the income and itemized deductions are large and very unequal, it may be more advantageous to file separately.

When filing jointly, both you and your spouse are equally responsible for the return and the taxes. If either one of the spouses understates the tax due, both are equally liable for the penalties unless the other spouse claims he or she was not aware of the mistake and did not benefit from it. Taxes can get pretty technical and tricky so if you or your spouse is having trouble determining tax liability, talk to an experienced tax preparer.