Things You'll Need
Copy of the original state tax form(s) you filed
Complete and sign Form 502XS, if applicable. Form 502XS is a simplified form that can be used to make certain changes to your original tax filing, including: wage totals; the amount of interest and dividends you claimed; switching from an itemized to a standard deduction; a new itemized deduction amount, due to income change. It can also be used for a change the amount of state taxes withheld or a change the number of exemptions claimed. If other changes must be made, use Form 502X.
Complete and sign Maryland Tax Form 502X, noting the needed changes. This form is similar in many respects to the original state tax form you filed, with some additional information requested. The tax form includes step-by-step instructions. You will want to have a copy of the original form(s) you filed for reference.
If you do not meet the requirement for
avoidance of interest for underpayment of estimated tax, obtain a Form 502UP for the tax year in question from any office of the Revenue Administration Division. Complete and attach it to your amended return. Enter any interest due on line 77 of Form 502X.
Attach a copy of your federal tax return, including any subsequent amendments.
Attach income statements, such as W-2s or 1099s, for any previously unclaimed income or withheld taxes.
Enclose payment for any additional tax owed to the state. Include interest, which must be computed and paid on any balance of tax due. Interest is due from the date the return was originally due to be filed to the date the tax is paid. Make your check or money order out to "Comptroller of Maryland" with the year of and type of tax noted on the memo line.
Mail return, attachments and payment to the following address:
Comptroller of Maryland
Revenue Administration Division