Maryland Form 505X, Nonresident Amended Tax Return

What is Maryland Form 505X?

Form 505X, Nonresident Amended Tax Return, is the Comptroller of Maryland form a nonresident uses to change a Maryland income tax return that has already been filed. If you are changing to resident status, the form says you must use Form 502X instead; the 2025 Form 502X instructions add that a nonresident who wishes to amend Form 515 must use Form 502X and a revised Form 505NR. The form above is the 2025 form (COM/RAD 022A, 09/25): a nine-page PDF with four form pages followed by five pages of instructions.

Use the form for the year you are amending. The Comptroller's filing information page says a nonresident who is amending should obtain a Form 505X and a nonresident tax booklet for the year they wish to amend, so that they have the proper instructions and rates. The 2025 form is for a 2025 return; for 2024, 2023, 2022 or 2021 use "Show form versions" above. The amounts, line numbers and addresses on this page are those of the 2025 form. As of October 2026 the Comptroller's website links the 2023, 2024 and 2025 forms and says to request a form prior to tax year 2022 by email at [email protected].

When a nonresident files Form 505X

The 2025 nonresident booklet (Instruction 31) says that if you need to change a return you have already filed, or if the IRS changes your return, you must file an amended return and include Form 505NR using the amended figures. The changes it lists are changes in income, filing status, amount of deductions, the number of exemptions, and the amount of additions to income and subtractions from income.

• Federal changes. If you file an amended federal return that changes your Maryland return, the booklet says you must file an amended Maryland return. If the IRS changes your federal return, you must notify Maryland within 90 days of the final determination.
• When to wait. The form's instructions say not to file an amended return until the original return has had time to be processed, at least six weeks for a current year return. The booklet adds that if you expect a refund from the original return, you should not file the amended return until you have received the refund check.
• Audit. Changes made as part of an amended return are subject to audit for up to three years from the date the amended return is filed.

Time limits

The nonresident booklet and Administrative Release 20 describe the three-year and two-year periods below as time limits for a claim for refund or credit of an overpayment. Reporting a change made by the IRS has its own deadlines (the last two exceptions in the list).

The instructions on the 2025 form say that, generally, Form 505X must be filed within three years from the date the original return was due (including extensions) or filed, with these exceptions:

• A claim filed after three years, but within two years from the time the tax was paid, is limited to the amount paid within the two years immediately before the claim is filed.
• A claim for refund based on a federal net operating loss carryback must be filed within 3 years after the due date (including extensions) of the return for the tax year of the net operating loss.
• A claim that results from a final determination of an administrative board, or from an appeal of one, made after those periods must be filed within one year of the final decision of the board or of the highest court to which an appeal is taken.
• If the IRS issues a final determination of adjustments that would decrease Maryland taxable income, the amended return is filed within one year after the final adjustment report or the final court decision if appealed. Administrative Release 20 limits a refund claim made on this basis to the changes made or accepted by the IRS, and the refund to the reduction in Maryland tax that results from the federal adjustment.
• If the IRS issued a final determination that would increase Maryland taxable income, the amended return is filed within ninety days after the final determination. The instructions also say that if your tax has been increased by the IRS, you must report the increase to the Revenue Administration Division within 90 days from the final IRS determination.

The 2025 nonresident booklet words the general rule as a limit on refund claims: generally, a claim for a refund or overpayment credit must be filed within three years from the date the original return was filed or within two years from the date the tax was paid, whichever is later; an original return filed early is considered filed on the date it was due; and a refund on a claim filed within the three years may not be more than the tax paid within the three years, plus any extension of time for filing, immediately before the claim.

The two wordings are not identical. The form's instructions point to the Comptroller's Administrative Release 20 for the refund limitations; the release (revised September 2009) words the general rule as the booklet does, three years from the date the original return was filed or two years from the date the tax was paid, whichever is later, and explains that Maryland law follows the periods in section 6511 of the Internal Revenue Code. The list above is not the whole release: it also has a rule for a claim based on a bad debt or worthless security (generally within 7 years after the due date of the return for the tax year in which the debt or security became worthless) and one for a taxpayer who has agreed with the IRS to extend the period for assessing federal income tax (a claim may be filed until 6 months after that period expires). If you are close to a limit, read the release and ask the Comptroller before you rely on a date.

How to fill out Form 505X

The instructions tell you to complete your federal return first, because most changes to the federal return change the Maryland return, and then to work through the form in this order:

1. Pages 3 and 4 first. Part I (income and adjustments from your federal return), Part II (itemized deductions, if you itemized) and Part III (the explanation of changes). In Part I the three columns are federal income (A), Maryland income (B) and non-Maryland income (C), each as corrected.
2. Then pages 1 and 2. Name, address, filing status and the questions on page 1; the tax computation on page 2, continued on page 3.
3. Columns A, B and C of the tax computation and of Part II. Column A takes the amounts as originally filed or as previously adjusted or amended, column B the net increase or net decrease for each line you are changing, column C the corrected amount. For an item you do not change, enter the column A amount in column C.
4. Part III. Enter the line number from pages 1 and 2 for each item you are changing and state the reason for the change.
5. Filing status. Generally, you may not change from married filing joint to married filing separately after the original due date of the return, and any change in filing status to or from married filing joint requires the signature of both spouses.

Figures printed in the 2025 form's instructions, for tax year 2025:

• Standard deduction. $3,350 if your filing status is single, dependent or married filing separately; $6,700 if it is married filing jointly, head of household or qualifying surviving spouse.
• Personal exemption. $3,200, reduced once federal adjusted gross income exceeds $100,000 ($150,000 if filing joint, head of household or qualifying surviving spouse with dependent child). The 2025 nonresident booklet says a dependent taxpayer may not claim a personal exemption.
• AGI factor. The instructions say you must adjust your standard or itemized deductions and exemptions using the AGI factor from their worksheet (Maryland adjusted gross income before subtraction of non-Maryland income, divided by federal adjusted gross income). The figures above are the amounts before that adjustment. Part II of the form points to Instruction 14 of the nonresident instructions for the factor; the 2025 nonresident booklet carries it to six decimal places, enters 1.000000 if the result is greater than that, and says to use 0 if Maryland adjusted gross income before subtractions is 0 or less, and 1 if federal adjusted gross income is 0 or less and the Maryland figure is greater than 0.
• Itemized deduction phaseout. If your federal adjusted gross income exceeds $200,000 ($100,000 for married individuals filing separately), your itemized deduction is subject to phaseout; the amount goes on line 9 of Part II.
• Net capital gain. Lines 9a and 10b apply an additional tax to certain net capital gain income of a filer who reported federal adjusted gross income of more than $350,000; line 10b multiplies line 9a by .02, and Form 502CG is attached.
• Result. The refund is line 25. A total amount due is line 28, to be paid in full with the return; the 2025 nonresident booklet says no payment of less than $1.00 is required.

For another tax year, take the figures from that year's form and booklet.

What to attach

• Form 505NR. The 2025 instructions carry the reminder to attach a revised Form 505NR to the 2025 amended nonresident return. The Comptroller's filing information page says to attach revised Forms 505 and 505NR. The 2025 nonresident booklet says to use Form 505X and Form 505NR to file an amended return and include a copy of your federal return.
• Federal amended return. If you are amending your federal return, attach a photocopy of the federal Form 1040X and any revised schedules.
• IRS adjustment. For a refund claim based on a final IRS adjustment report, Administrative Release 20 says the claim must include a copy of the final adjustment report from the IRS and, if the claim is based on an amended federal return, the amended federal return.
• Wage and tax statements. Attach Forms W-2, 1099s and K-1 to the front of the return if you are claiming additional Maryland withholding. Attach the forms, schedules and statements the instructions require; do not attach worksheets (the net operating loss worksheets that Instruction 13 asks for, below, are the exception).
• Dependents. Attach an amended Form 502B if you are changing dependent information.
• Sale of Maryland real property. Report the tax withheld from the proceeds on line 16 and attach a copy of your federal return with all schedules, statements and attachments, a copy of the HUD-1 Settlement Statement for the sale, and Form MW506NRS.
• Net operating loss. Check the carryback (farming loss only) or carry forward box on page 1 and attach copies of the federal loss year return and Form 1045, Schedules A and B. Instruction 13 words it as federal Form 1045 or 1040X, whichever was used for federal purposes, and Schedules A and B of Form 1045 or the equivalent worksheets used to develop the federal net operating loss.

Signing and sending the return

Signatures. The instructions say you must sign your return and both spouses must sign a joint return; the signature states, under the penalties of perjury, that the return and all attachments are true, correct and complete to the best of your knowledge and belief. If another person prepared the return, that person must also print their name, sign and enter their preparer's tax identification number (PTIN). Print the completed return and sign it; the form does not describe an electronic signature on a mailed return.

Where to mail the 2025 form. Page 4 of the form gives two addresses:

• Returns filed without payment: Comptroller of Maryland, Revenue Administration Division, 110 Carroll Street, Annapolis, MD 21411-0001.
• Forms that include payment: Comptroller of Maryland, Payment Processing, PO Box 8888, Annapolis, MD 21401-8888.

For a private delivery service such as FedEx or UPS, the instructions give this address: Comptroller of Maryland, Revenue Administration Division, 110 Carroll Street, Annapolis, MD 21411-0001.

The mailing section of the instructions gives the Carroll Street address with the added line "Amended Return Unit". A form for another year prints its own addresses; use the ones on the form you are filing. The instructions also say that sending the return by certified mail will not result in special handling and may delay your refund.

Payment. Make the check or money order payable to Comptroller of Maryland and write on it the last four digits of your Social Security number or Individual Tax Identification Number, the tax year and the tax type. Interest is due on any balance of tax from the date the return was originally due until the tax is paid; the 2025 instructions give the annual rate as 10.8133% through 12/31/26 and say it will change after that. No refund for less than $1.00 is issued, and the nonresident booklet says no payment is required when the amount due is less than $1.00.

Electronic filing. The instructions say you must file your amended Form 505X electronically to claim, or change information related to, business income tax credits from Form 500CR. The Comptroller's 2025 business forms page says Form 500CRW, a waiver request, must be submitted in order to file a paper version of Form 500CR.

Questions. The instructions give 1-800-638-2937, or 410-260-7980 from Central Maryland.

Maryland Form 505X resources

• Form 505X (2025), Comptroller of Maryland PDF
• Form 505NR (2025), Nonresident Income Tax Calculation, PDF
• Form 502X (2025), Amended Tax Return for residents, PDF
• 2025 Maryland Nonresident Tax Forms and Instructions (booklet), PDF
• Filing Information for Individual Income Tax, Comptroller of Maryland
• Administrative Release No. 20, Income Tax Refunds and Credits: Limitations, PDF
• Individual Tax Forms and Instructions, Comptroller of Maryland