Deductions & credits

No. If you meet all four criteria the spouses lived apart all year exception from Publication 555 (extracted below) and therefore there is no community property to divide, then you will not need to complete the form 8958.  You would select "No" when asked, "Do you have any community property adjustments?"  

" Spouses lived apart all year exception:

1. You and your spouse lived apart all year.
2. You and your spouse didn't file a joint return for a tax year beginning or ending in the calendar year.
3. You and/or your spouse had earned income for the calendar year that is community income.
4. You and your spouse haven't transferred, directly or indirectly, any of the earned income in condition (3) above between yourselves before the end of the year. Don't take into account transfers satisfying child support obligations or transfers of very small amounts or value."

Here are the income types that are not community property under the spouses lived apart all year exception.

• Earned income
• Trade or business income
• Partnership income or loss
• Separate property income
• Social security benefits.

Other income.

Treat all other community income, such as dividends, interest, rents, royalties, or gains, as provided under your state's community property law.

However, if you have items like interest and dividends earned on a joint account they also may not be considered community property under the "Community income not treated as community income" exception.  That exception reads:

"Community property laws may not apply to an item of community income that you received but didn't treat as community income. You are responsible for reporting all of that income item if:

• You treat the item as if only you are entitled to the income, and
• You don't notify your spouse of the nature and amount of the income by the due date for filing the return (including extensions)."

For example, you have a joint brokerage account with a 1099-Div that is issued to your social security number. You received the dividends and didn't share the dividends or share the form 1099-Div information, then you are not treating the income as community property.  The entire amount is reported as yours on your tax return and you are not making any adjustments.