Examination

• Audit Impact Study: The Specific Deterrance Implications of Increased Reliance on Correspondence Audits (2019 National Taxpayer Advocate Annual Report to Congress, B. Erard, Erich Kirchler, and Jerome Olsen)
• Audit Impact Study (2015 ARC, B. Erard and Associates)
• Identity Theft Case Review Report: A Statistical Analysis of Identity Theft Cases Closed in June 2014 (2014 ARC, TAS)
• Estimating the Impact Of Audits On The Subsequent Reporting Compliance Of Small Business Taxpayers: Preliminary Results (2014 ARC, TAS Research)
• Do Accuracy-Related Penalties Improve Future Reporting Compliance by Schedule C Filers? (2013 ARC, TAS Research)
• Research Prospectus: When Do Accuracy-Related Penalties Improve Future Reporting Compliance by Schedule C Filers? (2012 ARC, TAS Research)
• Math errors committed on individual tax returns: a review of Math errors issued on claimed dependents (2011 ARC, TAS Research)
• An analysis of the IRS examination Strategy: Suggestions to maximize compliance, improve credibility, and respect taxpayer rights (2011 ARC, TAS)
• A Framework for Reforming the Penalty Regime (2008 ARC, TAS Research)

Collection

• The IRS Can Systemically Identify Taxpayers at Risk of Economic Hardship and Screen Them Before They Enter Into Installment Agreements They Cannot Afford (2020 National Taxpayer Advocate Annual Report to Congress, TAS Research) – The majority of IRS installment agreements (IAs) with individual taxpayers are streamlined agreements, meaning that verification of a taxpayer’s financial circumstances is not required for certain amounts and lengths. These agreements place many taxpayers in a position where they cannot afford basic living expenses. The IRS established allowable living expenses (ALEs) to ensure that the satisfaction of their unpaid tax liabilities does not interfere with the ability to pay for those expenses necessary for basic living. This research study explores the effectiveness of an algorithm developed by TAS and based on systemically available information about the taxpayer’s income and likely ALEs. The study examines non-streamlined IAs for individuals initiated from fiscal year (FY) 2017 through most of FY 2020.
• A Study of the IRS Offer in Compromise Program for Business Taxpayers (PDF) (2018 National Taxpayer Advocate Annual Report to Congress, TAS)
• Further Analyses of “Federal Tax Liens and Letters:  Effectiveness of the Notice of Federal Tax Liens and Alternative IRS Letters on Individual Tax  Debt Resolution” (2018 National Taxpayer Advocate Annual Report to Congress, TAS)
• Study of Financial Circumstances of Taxpayers Who Entered Into Installment Agreements and Made Payments While Their Debts Were Assigned to Private Collection Agencies (2017 National Taxpayer Advocate Annual Report to Congress, TAS Research) – Since April 2017 the IRS outsourced the collection of certain tax debt to private collection agencies (PCA). This study reviews data on taxpayers with installment agreements (IAs) initiated while their debts were assigned to a PCA and who made a payment on their tax liability. The study includes a review of the financial circumstances of taxpayers in this program.
• A Study of The IRS Offer In Compromise Program (2017 National Taxpayer Advocate Annual Report to Congress, TAS Research) – In 2004, the Office of Program Evaluation and Risk Analysis (OPERA) completed a study of the IRS OIC program. This study, like the 2004 OPERA study, further analyzes earlier findings.
• The Importance of Financial Analysis in Installment Agreements (IAs) in Minimizing Defaults and Preventing Future Payment Noncompliance (2016 National Taxpayer Advocate Annual Report to Congress, TAS Research)
• IRS Should Use Its Internal Data to Determine If Taxpayers Can Afford to Pay Their Tax Delinquencies (2016 National Taxpayer Advocate Annual Report to Congress, TAS Research)
• Collecting Business Debts: Issues for the IRS and Taxpayers (2016 National Taxpayer Advocate Annual Report to Congress, TAS Research)
• IRS Collectibility Curve (2015 ARC, TAS Research)
• The IRS Private Debt Collection Program — A Comparison of Private Sector and IRS Collections While Working Private Collection Agency Inventory (2013 ARC, TAS Research)
• A Comparison of Revenue Officers and the Automated Collection System in Addressing Similar Employment Tax Delinquencies (2013 ARC, TAS Research)
• Investigating the Impact of Liens on Taxpayer Liabilities and Payment Behavior (2012 ARC, TAS)
• Research Prospectus: Comparing the Effect of Revenue Officers and the Automated Collection System on Future Compliance (2012 ARC, TAS)
• An Analysis of the IRS Collection Strategy: Suggestions to Increase Revenue, Improve Taxpayer Service, and Further the IRS Mission (2010 ARC, TAS)
• Estimating the Impact of Liens on Taxpayer Compliance Behavior: An Ongoing Research Initiative (2010 ARC, TAS Research)
• The IRS’s Use of Notices of Federal Tax Lien (NFTL) (2009 ARC, TAS Research)
• Effect of Tax Increase and Prevention Reconciliation Act of 2005 on IRS Offer in Compromise Program (2007 ARC, TAS Research)

Other Compliance Studies

• A Study of the IRS’s Use of the Allowable Living Expense Standards (2018 National Taxpayer Advocate Annual Report to Congress)
• Addressing the Cash Economy (2007 ARC, TAS Research)
• Criminal Investigation Refund Freeze Study (2005 ARC, TAS Research)

• Improving IRS Telephone Service: A Review of Best Practice Processes and Measures Used by Large Government and Private Sector Call Centers (2024 National Taxpayer Advocate Annual Report to Congress, TAS Research) – This report compares the telephone processes and metrics of the IRS with other public and private entities, including state and national governmental agencies that receive large call volumes. The goal of this comparison is to recommend metrics and processes that may improve IRS telephone operations.
• Taxpayer Opinions of IRS Individual Online Accounts and a Review of Online Accounts and Web Services Offered to Businesses and Tax Professionals by U.S. State and Foreign Country Taxing Authorities (2023 National Taxpayer Advocate Annual Report to Congress, TAS Research) – For part one, TAS engaged a contractor in 2023 to interview taxpayers to gain their insight and input on online accounts and their opinions about present and future online services along with views on account security requirements. For part two, as a continuation of the 2022 report, TAS Research completed a broad overview of state and foreign taxing authority websites in late 2023 with a focus on businesses and tax professionals. Specifically, TAS reviewed the IRS website along with websites of 48 U.S. states, the District of Columbia, Puerto Rico, and three countries – Canada, Australia, and the United Kingdom (“entities”). Each entity has a corporate income, gross receipts, or similar tax.
• A Review of Online Accounts and Web Services Offered by U.S. State and Foreign Country Taxing Authorities (2022 National Taxpayer Advocate Annual Report to Congress, TAS Research) – This research study is a broad review of the IRS website along with websites of 41 U.S. states that have an individual income tax, the District of Columbia, Puerto Rico, and three countries – Canada, Australia, and the United Kingdom (UK)  during 2022. Overall, the IRS website offered several services in common with U.S. states and the three countries reviewed, but there were notable differences.
• A Further Exploration of Taxpayers’ Varying Abilities and Attitudes Toward IRS Options for Fulfilling Common Taxpayer Service Needs (2017 National Taxpayer Advocate Annual Report to Congress, TAS Research) – This report, based on a telephone study, explores taxpayers’ use of IRS services, how they obtain them and how completely the service provided the information needed.  The study gathered information on the population’s access to and use of internet services at home, and typical use of online technology and repeats analyses from an earlier report.
• Taxpayers’ Varying Abilities and Attitudes toward IRS Taxpayer Service: The Effect of IRS Service Delivery Choices on Different Demographic Groups (2016 National Taxpayer Advocate Annual Report to Congress, TAS Research)
• The Service Priorities Project: Developing a Methodology for Optimizing the Delivery of Taxpayer Services (2013 ARC, TAS Research)
• Fundamental Changes to Return Filing and Processing Will Assist Taxpayers in Return Preparation and Decrease Improper Payments (2013 ARC, TAS)
• Options for Expanding the Remedies to Address Taxpayer Rights Violations (2012 ARC, TAS)
• Unlimit Innocent Spouse Equitable Relief (2010 ARC, TAS)
• Building a Better Filter: Protecting Lower Income Social Security Recipients from the Federal Payment Levy Program (2008 ARC, TAS Research)
• Taxpayer Needs, Preferences, and Willingness to Use IRS Services (2006 ARC, TAS Research)

• IRS Processing of Individual Taxpayer Identification Numbers (2024 National Taxpayer Advocate Annual Report to Congress, TAS Research) – This report examines the scope and impact of ITINs, focusing on the characteristics of ITIN-related tax returns, including the size of the ITIN tax return filing population, taxes paid, credits received, and other characteristics. It discusses the IRS administration of the program, including the challenge of the IRS reviewing and processing hundreds of thousands of ITIN applications. Finally, we look at the challenges faced by ITIN applicants, particularly when errors occur because the IRS erroneously deactivated their ITIN and the additional burdens imposed by the IRS issuance of ITIN-related math error notices, which taxpayers may not understand leading to delays and loss of millions of dollars in credits.
• Some Legitimate Taxpayers Did Not Receive a Tax Year 2020 Refund Because They Did Not Respond to an IRS Letter Requesting Identity Verification (2024 National Taxpayer Advocate Annual Report to Congress, TAS Research) – Last year, in conjunction with the National Taxpayer Advocate 2023 Annual Report to Congress, TAS published an online report describing a research project in which TAS contacted taxpayers likely eligible to receive their frozen tax year (TY) 2020 refunds. The TAS outreach study discussed in this report explored the effect of sending subsequent letters to a sample of potentially legitimate taxpayers who were likely entitled to their claimed refunds even though they had not authenticated their identity with the IRS in the past three years.
• Study of Potentially Legitimate Taxpayers Who Did Not Receive a Tax Year 2020 Refund Because They Did Not Respond to an IRS Letter Requesting They Verify Their Identity (2023 National Taxpayer Advocate Annual Report to Congress, TAS Research) – This report summarizes a recently implemented TAS Research study on taxpayers likely eligible for refunds the IRS froze because of suspected identity theft. Since 2021, the IRS only sends a single letter asking the taxpayer filing a return suspected of identity theft to authenticate their identity and verify their tax return , but each year, some taxpayers wait months to complete this process. TAS believes many legitimate taxpayers may be entitled to refunds still frozen and continue to be in limbo while the IRS has not processed their returns. As IRS procedures only require one letter notifying the taxpayers of a possible issue, TAS is exploring the effect of sending subsequent letters to a sample of likely legitimate taxpayers.
• Taxpayer Advocate Service Survey of Federal Government External Ombudsmen (2009 ARC, TAS Research)
• Downstream Impact Project: Identifying Drivers of TAS Workload (2006 ARC, TAS Research)

• A Conceptual Analysis of Pay-As-You-Earn (PAYE) Withholding Systems As a Mechanism for Simplifying and Improving U.S. Tax Administration (2018 National Taxpayer Advocate Annual Report to Congress, TAS)
• Do Taxpayers Respond to the Substantial Understatement Penalty? Analysis of  Bunching Below the Substantial Understatement Penalty Threshold (2018 National Taxpayer Advocate Annual Report to Congress, TAS)
• What Influence do IRS Audits Have on Taxpayer Attitudes and Perceptions? Evidence from a National Survey (2018 National Taxpayer Advocate Annual Report to Congress,  Erard, Kasper, Kirchler, and Olsen)
• Audits, Identity Theft Investigations, and Taxpayer Attitudes: Evidence from a National Survey (2017 National Taxpayer Advocate Annual Report to Congress, TAS Research)
• Do Taxpayers Respond to the Substantial Understatement Penalty Threshold? A Research Prospectus for an Analysis of Bunching Below the Penalty Threshold (2017 National Taxpayer Advocate Annual Report to Congress, TAS)
• Understanding The Hispanic Underserved Population (2015 ARC, TAS)
• Low Income Taxpayer Clinic Program: A Look at Those Eligible to Seek Help From the Clinics (2014 ARC, TAS)
• Small Business Compliance: Further Analysis of Influential Factors (2013 ARC, TAS Research)
• Factors Influencing Voluntary Compliance by Small Businesses: Preliminary Survey Results (2012 ARC, TAS Research)
• TeleFile-Taxpayers’ Characteristics and Filing Behaviors (2010 ARC, TAS)
• Researching the Causes of Noncompliance: An Overview of Upcoming Studies (2010 ARC, TAS)
• Subsequent Compliance Behavior of Delinquent Taxpayers: A Compliance Challenge Facing the IRS (2009 ARC, TAS)
• An Analysis of Tax Administration Issues Raised by a Consumption Tax, Such as a National Sales Tax or Value Added Tax (2009 ARC, TAS)
• The Need to Increase Preparer Responsibility, Visibility and Competence (2008 ARC, Leslie Book)
• Aspects of Tax Compliance (2007 ARC and 2007 8 FLA. Tax Rev. 601, Normative and Cognitive Aspects of Tax Compliance: Literature Review and Recommendations for the IRS Regarding Individual Taxpayers – A Morale Approach to Compliance: Recommendations for the IRS, Marjorie E. Kornhauser)
• Preparers Role in Tax Compliance (2007 ARC, Study of the Role of Preparers in Relation to Taxpayer Compliance with Internal Revenue Laws, Leslie Book)

• Study of the Extent to Which the IRS Continues to Erroneously Approve Form 1023-EZ Applications (2019 National Taxpayer Advocate Annual Report to Congress, TAS)
• An Analysis of Tax Settlement Programs as Amnesties (2017 National Taxpayer Advocate Annual Report to Congress, TAS) – Research generally suggests broad and frequent one-size-fits-all amnesties can reduce government revenues in the long run. They can reduce future compliance by eroding perceptions of fairness, revealing noncompliance norms, or diluting economic deterrence. This discussion reviews amnesty research to evaluate settlement programs to minimize unnecessary burdens and disputes, and improve future compliance.
• 2016 IRS Nationwide Tax Forums TAS Focus Group Report (2016 ARC, TAS)
• Study of Taxpayers That Obtained Recognition As IRC § 501(C)(3) Organizations On The Basis of Form 1023-EZ (2015 ARC, TAS)
• From tax collector to Fiscal automaton: demographic History of Federal income tax administration, 1913-2011 (2011 ARC, TAS)
• Analyzing pay-as-you-earn Systems as a path for Simplification of the U.S. Tax System (2011 ARC, TAS)
• The Patient Protection and Affordable Care Act: A Preliminary Analysis of the Challenges Facing the IRS in Implementing Health Care Reform (2010 ARC, TAS)
• Evaluate the Administration of Tax Expenditures (2010 ARC, TAS)
• Running Social Programs through the Tax System (2009 ARC, TAS)

TAS produces taxpayer statistics for each Congressional District in each of the tax years listed below. Each state is listed on a separate sheet containing state totals followed by a breakdown for each congressional district. The totals are stratified by income levels listed at the top of each sheet. The year included in the file names shown below designates the tax year for the return. Typically a tax return is filed in the year following the tax year, for example, a 2014 Tax Year return is not filed until 2015 (calendar year) or later.

• 2018 Statistics (.zip Excel file)
• 2017 Statistics (.zip Excel file)
• 2016 Statistics (.zip Excel file)
• 2015 Statistics (.zip Excel file)
• 2014 Statistics (.zip Excel file)
• 2013 Statistics (.zip Excel file)
• 2012 Statistics (.zip Excel file)
• 2011 Statistics (.zip Excel file)
• 2010 Statistics (.zip Excel file)
• 2009 Statistics (.zip Excel file)