• It's not  yet official whether the IRS will consider marriage rights to be retroactive.  We are thinking  the IRS  will resolve this point and other issues  by Oct.  After that we will start to file amended returns if it is allowed and beneficial.
• We also do not know yet if the IRS will treat registered domestic partners  as married.
• For tax year 2013, we expect to start filing same sex married couples using the married-joint filing status for anyone who is married as of Dec 31, 2013.  
• Married-separate is also an option but that usually results in higher overall tax and is generally less advantageous.  
• A same sex married couple will not be allowed to continue to file as single starting in 2013.
• See Tax Tips for Newlyweds from the IRS below.
• Not everyone will benefit from filing a joint return.  Every situation is different.  Generally married joint filing status will result in  lower  taxes where there is a lop-sided division of income such as pension or IRA income which is all or mostly allocated to one person.
• Finally, if you're thinking about getting married now that Prop 8 is gone, here are some tax tips from the IRS for newlyweds that would apply equally to same sex and opposite sex couples:

Tax Tips for Newlyweds (from the IRS)

Late spring and early summer are popular times for weddings. Whatever the season, a change in your marital status can affect your taxes. Here are several tips from the IRS for newlyweds.

• It’s important that the names and Social Security numbers that you put on your tax return match your Social Security Administration records. If you’ve changed your name, report the change to the SSA. To do that, file Form SS-5, Application for a Social Security Card. You can get this form on their website at SSA.gov, by calling 800-772-1213 or by visiting your local SSA office.

• If your address has changed, file Form 8822, Change of Address to notify the IRS. You should also notify the U.S. Postal Service if your address has changed. You can ask to have your mail forwarded online at USPS.com or report the change at your local post office.
• If you work, report your name or address change to your employer. This will help to ensure that you receive your Form W-2, Wage and Tax Statement, after the end of the year.
• If you and your spouse both work, you should check the amount of federal income tax withheld from your pay. Your combined incomes may move you into a higher tax bracket. Use the IRS Withholding Calculator tool at IRS.gov to help you complete a new Form W-4, Employee's Withholding Allowance Certificate. See Publication 505, Tax Withholding and Estimated Tax, for more information.
• If you didn’t qualify to itemize deductions before you were married, that may have changed. You and your spouse may save money by itemizing rather than taking the standard deduction on your tax return. You’ll need to use Form 1040 with Schedule A, Itemized Deductions. You can’t use Form 1040A or 1040EZ when you itemize.
• If you are married as of Dec. 31, that’s your marital status for the entire year for tax purposes. You and your spouse usually may choose to file your federal income tax return either jointly or separately in any given year. You may want to figure the tax both ways to determine which filing status results in the lowest tax. In most cases, it’s beneficial to file jointly.

• For more information about these topics, visit IRS.gov. You can also get IRS forms and publications at IRS.gov or by calling 800-TAX-FORM (800-829-3676).

Tags: DOMA