Form IT-225-I: Instructions for Form IT-225 New York State Modifications (Tax Year 2025)

Form IT-225-I is the instruction booklet issued by the New York State Department of Taxation and Finance to help taxpayers correctly complete Form IT-225, New York State Modifications. If your federal adjusted gross income doesn’t match what New York State requires you to report, this form is where you make those corrections. The instructions walk through every addition and subtraction code you might need, and they’re essential reading before you sit down with the actual IT-225 form.

New York, like many states, doesn’t simply accept your federal tax return numbers as-is. The state has its own rules about certain types of income, deductions, and credits that differ from federal treatment. Form IT-225 is the mechanism for reconciling those differences, and IT-225-I explains exactly how to do it, line by line, code by code.

What This Form Covers

The instructions break down two broad categories: additions and subtractions. Additions are amounts New York requires you to add back to your federal income because the state doesn’t recognize a federal exclusion or deduction the same way. Subtractions work the other direction — income that’s taxable federally but exempt or treated differently under New York law.

Common examples include certain interest income from other states’ municipal bonds, specific pension and annuity adjustments, college savings program contributions or withdrawals, and various business-related modifications tied to New York’s decoupling from certain federal provisions. Each modification has its own alphanumeric code (like A-201 or S-103), and the instructions list them all with explanations of who qualifies and how to calculate the amount.

Who Needs to File Form IT-225

Not every New York taxpayer needs this form. You’ll need it if any of these situations apply to you:

• You have income or deductions that New York treats differently than the federal government does
• You’re a partner, shareholder, or beneficiary receiving modifications passed through from a partnership, S corporation, or estate/trust
• You need to report additions or subtractions that don’t have a dedicated line elsewhere on your main New York return
• You’re filing as a nonresident or part-year resident with New York-source modifications

If none of the listed addition or subtraction codes apply to your situation, you likely don’t need to file this form at all. The instructions include a summary table early on that helps you quickly check whether any codes match your circumstances before you commit to filling out the whole form.

When You’ll Use This Form

Form IT-225 gets filed alongside your main New York State personal income tax return (IT-201, IT-203, or IT-205 depending on your filing situation) for tax year 2025. It’s not a standalone filing — it’s a supporting schedule that feeds numbers into your primary return. If you’re also claiming certain credits, you may find yourself cross-referencing related instruction sets, such as those for Form IT-252-I covering the investment tax credit for financial services, since some modification codes tie directly into credit calculations elsewhere on your return.

How to Get and Complete It

Form IT-225-I is a print-and-fill document — there’s no digital fillable version available. You’ll need to download the PDF from the Department of Taxation and Finance, print it out, and complete Form IT-225 by hand using the instructions as your reference guide. Once filled out, it attaches to your paper return or gets referenced when e-filing through approved software that supports these modification codes.

Start by reading through the addition and subtraction code lists to identify which ones actually apply to you. Many taxpayers only need one or two codes rather than working through the entire booklet. Pay close attention to any code that involves pass-through entities, since those often require documentation from the partnership or S corporation issuing your K-1.

If you’re dealing with a change in residency status during the tax year, you might also need to review Form IT-260-I for special accrual rules, since residency changes often trigger specific modification codes on IT-225 related to accrued income and deductions. Similarly, homeowners dealing with mortgage recording tax credits may find overlap with modifications covered in Form IT-256-I.

Double-check your entries against your federal return before submitting. Errors on modification codes are a common reason for processing delays or notices from the department, since mismatched numbers between your federal and state filings tend to trigger automatic review.