Notice of Additional Tax Due series

You received a New York Notice of Additional Tax Due because the Tax Department reviewed your account and determined that you owe more than your return reported. This is a proposed or assessed change, not just a reminder to pay what you already admitted owing. The state is telling you that, based on its records, the correct tax is higher, and it is adding that difference plus interest and often a penalty. The reason can be many things. New York may have matched your return against wage and information statements and found income that was not reported. It may have disallowed a credit, deduction, or exemption. It may have corrected a math or transcription error. For a business, it may reflect a sales tax adjustment after comparing reported taxable sales to other data, a withholding shortfall, or a corporation tax change tied to apportionment, the fixed dollar minimum, or a mandatory first installment. The notice itself carries the real explanation. The first page shows a notice date, an assessment or case number, the tax type, the tax period, the amount of additional tax, and an explanation of the basis for the change. The federal version of this is the IRS proposing additional tax, and the broader collection framework that follows an unpaid balance is described at https://www.irs.gov/businesses/small-businesses-self-employed/the-collection-process . Here is a worked example. A taxpayer files a 2024 New York return reporting 80,000 dollars of wages. New York matches information statements and finds an additional 9,000 dollars of reported income from a brokerage that was left off, recomputes the tax, and issues a Notice of Additional Tax Due for 620 dollars of extra tax plus interest in May 2026. A common mistake is paying the new amount immediately to make the letter go away, even when the underlying change is wrong. If New York double counted income that was already on the return under a different line, paying simply hands over money you did not owe. An edge case worth watching. Some additional tax due notices are proposed and give you a clear protest window before the amount becomes final, while others arrive after a proposed change you did not answer, which means the window may already be running or closed. The wording on your notice tells you which one you are holding, and that distinction changes everything about how you respond. If the basis for the change is not obvious from the page, our team can decode it against your filed return. A further point that trips people up is the difference between a notice that proposes additional tax and one that has already assessed it. A proposed notice invites a response and holds off on collection. An assessed notice means the change is on your account now and interest is already running, which raises the stakes of a slow reply. Reading which one you hold is the first real decision, and the language on the page makes it clear if you look for the protest section. Start at https://reedcorp.tax/new-client-inquiry/ and we will identify exactly what New York adjusted, whether the change is proposed or assessed, and whether the adjustment holds up against the return you actually filed.

The first move after a Notice of Additional Tax Due is to read the explanation section and figure out exactly what New York changed, then compare that change against your filed return and your records before you agree or disagree. Do not pay on reflex and do not toss it aside. This notice usually carries a protest deadline, so the calendar matters from day one. Write down the notice date, the protest or response deadline printed on the page, the tax type, the tax period, the assessment or case number, and the amount of additional tax, interest, and penalty broken out separately. Then pull the return for that period and the documents behind the line New York adjusted. If the change is added income, gather the wage and information statements and confirm whether that income was already reported somewhere on the return. If a credit or deduction was disallowed, find the proof that supports it, such as receipts, a dependent record, or a credit worksheet. For a business sales tax change, compare gross sales, taxable sales, exempt sales, and use tax against the period in question. New York explains how to respond to a letter requesting additional information and how to disagree with a bill or action at https://www.tax.ny.gov/tra/disagree.htm . The federal counterpart, if you are also weighing whether to appeal a similar federal change, is the IRS Independent Office of Appeals at https://www.irs.gov/appeals , and if you simply owe and need time the federal route is the installment agreement at https://www.irs.gov/payments/online-payment-agreement-application . Here is a worked example with dates. A taxpayer receives a Notice of Additional Tax Due dated April 6, 2026 assessing 1,450 dollars for tax year 2023 after New York disallowed a college tuition credit. The taxpayer pulls the Form 1098-T and tuition receipts, confirms the credit was valid, and decides to dispute rather than pay. They calendar the protest deadline immediately. The common mistake is calling the department, getting told the change looks routine, and assuming that call paused the deadline. It did not. Contacting the department does not extend a protest deadline set by the notice. An edge case. If you partly agree, you can pay the part you accept and protest the part you dispute, which stops interest from running on the agreed portion while you fight the rest. Sorting the agreed amount from the disputed amount is the kind of line drawing that decides how much you ultimately pay. If you are not certain whether to pay or protest, bring the notice and the return to us first. A second edge case is a change driven by an information statement you never received, such as a corrected brokerage form. In that situation the proof you need lives with the third party, and requesting it early matters because the protest clock does not wait for paperwork to arrive. A third practical step is to recompute the tax yourself or with your preparer using the adjustment New York made, so you can see whether the dollar figure is even arithmetically right before you decide to fight it. New York adjustments are sometimes correct in concept but wrong in amount. Begin at https://reedcorp.tax/services/irs-audit-refund-notice-assistance/ and we will tell you whether the adjustment is defensible, and if so for how much, before any deadline closes.

You dispute a Notice of Additional Tax Due by filing a protest before the deadline printed on the notice, and in New York the most common protest is a request for a conciliation conference through the Bureau of Conciliation and Mediation Services. BCMS is an independent bureau inside the Tax Department that reports directly to the Commissioner, and it exists to resolve disputes without a formal hearing. You request the conference using Form CMS-1-MN, and your request must arrive by the deadline on the notice. The Tax Department states plainly that it cannot accept a request submitted after that deadline and that these time limits are set by the Tax Law and cannot be extended. New York reports that taxpayers file the large majority of all protests as conciliation requests and resolve most of them through that process, which makes it the practical starting point for most people. You can read New York guidance on disagreeing with a bill or action at https://www.tax.ny.gov/tra/disagree.htm . The other route is a petition to the Division of Tax Appeals, a more formal venue with an administrative law judge, which some taxpayers choose directly and others reach after a conciliation conference does not resolve the matter. The federal parallel for a proposed change is working through the IRS Independent Office of Appeals at https://www.irs.gov/appeals , and the federal lien and levy consequences of leaving a balance unresolved are described at https://www.irs.gov/businesses/small-businesses-self-employed/understanding-a-federal-tax-lien . Here is a worked example. A consultant receives a Notice of Additional Tax Due dated March 16, 2026 for 3,200 dollars after New York added unreported 1099 income that was actually a duplicate of income already on the return. Before the deadline, the consultant files Form CMS-1-MN, attaches the return showing the income was reported, and explains the duplication. BCMS assigns a CMS number, sends an acknowledgment in roughly 10 days, and schedules a conference with at least 30 days written notice. The common mistake is treating the conference as a court date that requires a lawyer and perfect briefs. It is an informal discussion, and a clear one page explanation with the supporting documents often carries the day. An edge case. If your protest deadline is days away and your records are incomplete, file the conciliation request on time anyway and supplement the file during the process, because filing late forfeits the right entirely. Missing the date is the one error you cannot undo. A second edge case is a protest that covers more than one period or more than one issue. You can raise several adjustments in a single conciliation request, but each one needs its own supporting record, and mixing them without organizing the proof per issue tends to slow the review. A third point is that the conference officer can settle on a number between full agreement and full disagreement, so going in with a clear fallback position, not just an all or nothing demand, often produces a better result. A short cover note that states what you dispute, why, and what the corrected figure should be gives the officer a place to start. If you want help preparing the protest so it lands the first time, our firm prepares conciliation requests and represents taxpayers through BCMS. Reach us at https://reedcorp.tax/services/irs-audit-refund-notice-assistance/ .

Ignoring a Notice of Additional Tax Due lets the proposed or assessed amount harden into a final balance, and once it is final New York can collect it the same way it collects any other tax debt. The additional tax does not disappear because you set the letter aside. If the notice carried a protest window and you let it pass, you generally lose the easy right to argue the change through a conciliation conference or the Division of Tax Appeals, and the amount becomes fixed and final. From there the path runs straight into collection. New York can issue a Notice and Demand, and if that goes unpaid it can file a tax warrant, which creates a lien against your property and opens the door to a levy on your bank account or an income execution against your wages. New York describes paying a bill or notice at https://www.tax.ny.gov/pay/pay-bill.htm . Interest also keeps accruing daily the entire time the balance sits open, so a disputed 1,500 dollar change that you might have beaten can grow into a larger fixed debt that you can no longer challenge. The federal system follows the same logic. An unresolved federal balance leads to a statutory lien and the IRS can perfect and enforce it, as explained at https://www.irs.gov/businesses/small-businesses-self-employed/understanding-a-federal-tax-lien , and the IRS levy power over bank accounts and wages is described at https://www.irs.gov/businesses/small-businesses-self-employed/levy . Here is a worked example with dollars and dates. A taxpayer receives a Notice of Additional Tax Due dated February 9, 2026 for 2,100 dollars based on a disallowed deduction, ignores it, and the protest window closes in spring 2026. The amount becomes final, a Notice and Demand follows, and by autumn a tax warrant is filed and a bank levy freezes funds. The deduction the taxpayer could have proven is now off the table, because the time to dispute it ran out. The common mistake is assuming the burden stays on New York to prove its case forever. Once the protest window closes, the practical burden shifts to you to pay, and your room to dispute the change is gone. An edge case. Even after the amount is final you can still pursue payment relief such as an installment payment agreement, and in some hardship situations an offer in compromise, but those address how you pay, not whether the underlying change was right. A second edge case is that a finalized error can sometimes be reopened on narrow grounds, but that is a steep and uncertain path compared to a timely protest. A third point people miss is that ignoring one period often invites scrutiny of others. When New York adjusts a return and the taxpayer never responds, the same issue can surface in adjacent years, and a pattern of silence can turn one notice into several. The far better outcome is to respond before the window closes, even if the response is only a timely conciliation request that buys room to gather proof. If a deadline is near or already missed, contact us quickly so we can preserve whatever options remain, because the menu of choices shrinks the moment the protest window shuts. Start at https://reedcorp.tax/services/tax-compliance/ and bring the notice and the return for the period in question.

A Notice of Additional Tax Due is New York saying you owe more than you reported, and the federal system has a direct counterpart in the way the IRS proposes and then assesses additional tax. Federally, when the IRS determines additional tax it typically sends a proposed change, and once the tax is assessed it issues a notice and demand for payment under Internal Revenue Code section 6303, which starts the federal collection process described at https://www.irs.gov/businesses/small-businesses-self-employed/the-collection-process . The dispute timing is the part people most often misunderstand, because both systems give you a window to challenge a proposed change before it becomes final, and both windows are unforgiving once they close. In the federal system you generally work a proposed change through the IRS Independent Office of Appeals at https://www.irs.gov/appeals , and if the balance is correct but unaffordable you can request an installment agreement at https://www.irs.gov/payments/online-payment-agreement-application . New York routes the same kind of dispute through the Bureau of Conciliation and Mediation Services using Form CMS-1-MN, or through a Division of Tax Appeals petition, and the deadline on the notice cannot be extended, as New York explains at https://www.tax.ny.gov/tra/disagree.htm . The collection consequences also mirror each other. An unresolved federal balance produces a federal tax lien and possible levy, while an unresolved New York balance produces a tax warrant and possible levy or income execution. Here is a worked example of the two side by side. A taxpayer gets an IRS proposed change adding 5,000 dollars of tax for 2023 and, a few months later, a New York Notice of Additional Tax Due adding 700 dollars for the same year, because the state often piggybacks on a federal adjustment to income. The taxpayer disputes the federal change through IRS Appeals and, separately, files a conciliation request with BCMS on the New York piece before its own deadline. Winning one does not automatically win the other, so both have to be worked. The common mistake is assuming that a federal correction flows to New York on its own. It does not happen automatically, and the New York deadline runs on its own schedule regardless of where the federal case stands. An edge case. If you ultimately amend the federal return or the IRS changes your income, New York may need a corresponding adjustment, and you generally must report a federal change to New York within a set time. A second edge case is that the New York interest and penalty rates differ from the federal ones, so the cost of waiting is not identical on the two balances. Because these tracks move in parallel and on different clocks, handling them together avoids a missed state deadline while you focus on the federal case. A third practical difference is documentation. The proof that satisfies IRS Appeals on a federal income adjustment is usually the same proof New York wants on its piggyback adjustment, so assembling one clean package can serve both cases. Building that package once, rather than twice, is where coordinating the two notices pays off. Our firm works federal and New York adjustments as one matter. Start at https://reedcorp.tax/services/individual-tax-returns-1040/ and bring both notices so nothing slips between the two systems and so the same supporting records do double duty.