1.26 Ark. Code R. 51-504(a)
When the gross income of an Arkansas resident includes income derived from sources outside the State of Arkansas, such as property or business activity, the Arkansas income tax liability shall first be computed as if all of the Arkansas resident's income was derived from sources within the State of Arkansas. However, a credit shall be allowed against the resident's Arkansas income tax liability in the amount of any income tax actually owed by the resident for the tax year at issue to any other state or territory.
Any credit given shall not be allowed to exceed what the tax would be on all the Arkansas resident's income, from wherever derived, if such tax was calculated using Arkansas income tax rates. No credit shall be allowed against the resident's Arkansas income tax liability unless the resident can clearly show that he or she would be subject to double taxation on a portion of his or her income unless the credit is allowed.
Example: Mr. and Mrs. Jones file a full year resident return in the state of Arkansas. Mr. Jones works in Arkansas and earns $30,000. Mrs. Jones works in Oklahoma and also earns $30,000. Mrs. Jones paid $1,500 tax to Oklahoma. The Jones' file as status "4" married filing separate on same return.
* The other state tax credit is limited to what the amount of Arkansas tax would be if the Oklahoma income was earned in Arkansas
The Jones' must attach a copy of their Oklahoma tax return to their Arkansas tax return in order to receive this credit.
1.26 Ark. Code R. 51-504(a)