Taxpayers that were residents of Louisiana for the entire year are allowed a credit for the net income taxes properly paid to another state of the United States. A credit may not be claimed for taxes paid to cities, the District of Columbia, or foreign countries. Credits are only allowed on your Louisiana return if they are for the same taxable year for which the tax was paid to another state or in the succeeding taxable year.
The credit for taxes paid to another state is automatically calculated in your account when you add a Nonresident/Part-year resident return to your already created Resident/Part-Year Resident Louisiana return if you pay taxes to both Louisiana and another state.
For more information please see the Louisiana DOR website here.