INSTRUCTIONS: MARYLAND AMENDED CORPORATION INCOME TAX RETURN (Form 500X)
Maryland corporations which need to amend a previously filed income tax return should do so within three years using a form 500X. The form is found on the website of the comptroller of Maryland.
Maryland Amended Corporation Income Tax Return 500X Step 1: Enter the fiscal year beginning and ending dates of the applicable period if not filing on a calendar year basis.
Maryland Amended Corporation Income Tax Return 500X Step 2: Give your corporation's current name, address and federal employer identification number (FEIN). If different from the one on your original return, enter the original name, address and FEIN on the right where indicated.
Maryland Amended Corporation Income Tax Return 500X Step 3: Answer the six questions below about the reason for your amended return by checking "yes" or "no."
Maryland Amended Corporation Income Tax Return 500X Step 4: Lines 1 through 10e require you to provide the originally entered values in column A, the net increase or decrease between that and your corrected figures in column B, and the corrected amount in column C. Document your income as instructed on lines 1 through 5.
Maryland Amended Corporation Income Tax Return 500X Step 5: Skip to Part C on the second page to calculate your Maryland apportionment factor. Transfer the result from line 5 of this section line 6 of the first page.
Maryland Amended Corporation Income Tax Return 500X Step 6: Multiply line 5 by line 6 and enter the results on line 7.
Maryland Amended Corporation Income Tax Return 500X Step 7: Calculate your tax owed on lines 8 and 9 as instructed.
Maryland Amended Corporation Income Tax Return 500X Step 8: Document taxes paid and applicable credits on lines 10a through 10e.
Maryland Amended Corporation Income Tax Return 500X Step 9: Complete lines 11 through 15 as instructed to determine your balance or refund due.
Maryland Amended Corporation Income Tax Return 500X Step 10: If you are filing late, calculate your interest and penalty due as instructed on line 16. Enter your final total due on line 17.
Maryland Amended Corporation Income Tax Return 500X Step 11: In part D on the second page, provide a full explanation of all amended numbers. Include the line number for every change. Attach all supporting documentation. An officer should sign and date the form.
