Will Form 990 satisfy an organization’s state reporting requirements?

State reporting requirements are determined by the individual states. Many states require certain tax-exempt organizations to file a Form 990 or Form 990-EZ. Accordingly, organizations should check with their respective states to determine their state filing obligations. 
Appendix I ( Form 990 instructions), Use of Form 990 or 990-EZ to Satisfy State Reporting Requirements, addresses various differences between IRS and state filing requirements.