Contents

• Data Products and General Release Schedule
• IRS Methodology and Limitations
• Disclosure Protection Procedures
• Data Available by State and Local Area Tabulation
• Congressional District Tabulation Specifics
• Location
• Publication Schedule, Format, and Years Available
• Tabulation-Specific Methodology and Limitations
• State Tabulation Specifics (Individual Income Tax)
• Location
• Publication Schedule, Format, and Years Available
• Tabulation-Specific Methodology and Limitations
• State Tabulation Specifics (Estate Tax)
• Location
• Publication Schedule, Format, and Years Available
• Tabulation-Specific Methodology and Limitations
• County, Metropolitan, and Micropolitan Area Tabulation Specifics
• Location
• Publication Schedule, Format, and Years Available
• Tabulation-Specific Methodology and Limitations
• ZIP Code Area Tabulation Specifics
• Location
• Publication Schedule, Format, and Years Available
• Tabulation-Specific Methodology and Limitations
• U.S. Population Migration Data, by State and by County
• Location
• Publication Schedule, Format, and Years Available
• Tabulation-Specific Methodology and Limitations

Summary

This report summarizes data currently available from the Internal Revenue Service (IRS) on individual and estate tax filings tabulated by state, congressional district, ZIP code, county, and metro area. The IRS collection of U.S. population migration data through individual income tax filings is also discussed. This report reviews the methodology, data limitations, and expected publication schedules specific to each level of geography. Tables are provided listing the IRS form and line numbers of source data contained within each tabulation. This report is intended as a reference document to assist with navigation of the IRS's SOI tables and to facilitate access to the data contained within.

The Internal Revenue Service (IRS) publishes statistical data related to individual, business, and estate income tax filings. Generally, IRS Statistics of Income (SOI) publications tabulate¹ data at the national level. However, select data are tabulated for smaller geographical areas including by state, county, metro area, ZIP code, and congressional district. This report details currently available publications of subnational tabulations. Depending upon the volume and complexity of the statistics, tables for a given year may be available prior to the end of the taxable year (projections) or may not be available until several years after the end of the taxable year (e.g. data from individual Form W-2 data tabulations). The IRS statistical website commingles current compilations with historical data archives. This report discusses and highlights the current available data series.

For the purposes of this report, tabulations of geographic areas at a level smaller than the state level (ZIP code, congressional district, county, and metro area) are categorized and referred to as local area tabulations.

Data Products and General Release Schedule

Table 1 summarizes the type of tax return data currently available at subnational geographic areas, the update cycle, and the expected release period and delay between tax year data and publication. For specific data included in each type of tax return publication, see Table 3 (data from individual income tax returns), Table 5 (data from estate tax returns), and Table 6 (taxpayer migration data).

The IRS publishes both a yearly expected release schedule² and separate quarterly updates to the expected release schedule.³ Updates to published release dates and recently released publications are listed on the SOI's "What's New" page.⁴

IRS Methodology and Limitations

This section addresses statistical sampling methodology and related limitations generally applicable to state and local area tabulations. See specific information for each individual tabulation in this report for additional methodological notes.

Tabulations are based on individual income tax returns filed with the IRS during the calendar year following the tax year.⁵ While the bulk of returns filed during this 12-month period are primarily for the immediately prior tax year, the IRS receives some returns for tax years before the immediately prior tax year.⁶ These late-filed returns for earlier tax years that are filed during the 12-month data collection period are used as a substitute and proxy for the smaller number of returns that are typically filed beyond the expiration of the collection period.⁷

Data do not represent the full U.S. population, because many individuals are not required to file individual income tax returns.⁸ For reference, for the 2022 tax year, the IRS received individual income tax filings for just over 214 million adults.⁹ Meanwhile the U.S. Census Bureau estimated the adult population of the United States to be over 257 million.¹⁰

State totals within specific local area data tabulations may not be comparable to state totals published in other SOI products. This lack of comparability is due to disclosure protection procedures or other exclusions that impact data reported in other SOI products.¹¹ For instance, tax returns filed without ZIP codes and returns filed with ZIP codes that did not match the state codes shown on the returns are excluded from local area tabulations.¹² Additionally, state and local area tabulations are calculated using the locations of the addresses on the tax returns, which may differ from taxpayers' actual or current residences.¹³

For tax years 2020 and 2021, individual income tax returns filed for the exclusive purpose of receiving economic impact payments (stimulus payments) were excluded from the data.¹⁴

Tax returns filed using Army Post Office (APO) and Fleet Post Office (FPO) addresses; foreign addresses; and addresses in Puerto Rico, Guam, the U.S. Virgin Islands, American Samoa, the Marshall Islands, the Northern Marianas, and Palau are excluded from local area tabulations.¹⁵ Returns from Puerto Rico are tabulated at the state level. Returns listing APO addresses, FPO addresses, and geographic locations other than states, the District of Columbia, or Puerto Rico are tabulated as one area and published with the location title of "other areas" at the state tabulation level.¹⁶

Relative to the national tabulations, those done for state and local geographic areas represent smaller populations and use a smaller number of income bands for categorizing returns by adjusted gross income (AGI).¹⁷ The AGI bands used for state, congressional district, ZIP code, and county and metro area data tabulations are shown in Table 2.

Disclosure Protection Procedures

The IRS is required¹⁸ to prevent disclosure, directly or indirectly, of information specific to individual taxpayers or businesses.¹⁹ Therefore, SOI publications implement disclosure protection procedures to ensure taxpayer confidentiality in publicly available data. This section addresses the disclosure protections generally applicable to state and local area tabulations, including when specific data may be excluded, suppressed, collapsed, or rounded. Please refer to the specific information for each individual tabulation for additional disclosure procedures.

• Income and tax items with fewer than a set number of returns (10 returns for state tabulations or 20 returns for local area tabulations) for a particular AGI band are combined (or "collapsed") with another AGI band within the same locality being measured (congressional district, ZIP code, state, or county or metro area). Collapsed AGI classes are identified with a double asterisk (**) in the SOI Excel files.²⁰
• Income and tax items with fewer than 20 returns for an entire local tabulation area are excluded.²¹
• If an income or tax item from one return constitutes more than a specified threshold percentage of the total of any particular reported number (the actual threshold percentage cannot be released),²² the specific data item for that return is excluded from that reported number. For example, if the amount for wages from one return represents 75% of the value of the total for that cell, the data item will be suppressed.
• The number of returns listed, when paired with a value amount, have been rounded to the nearest 10.²³ The number of returns listed, when not paired with a value amount, may not have been rounded.²⁴

As mentioned previously, due to these disclosure protection procedures, statewide totals may not be comparable across different tabulations.

Data Available by State and Local Area Tabulation

Table 3 identifies the individual income data included in current state and local area tabulations by IRS form and line. Recent additions to available data are noted along with the tax year of their first inclusion. Due to changes in legislation and tax forms, specific data available in previous years may no longer be available in current publications. Recent removals of previously available data are noted in Table 4 by form, line, and last year of inclusion. These tables track only newly included or excluded data points and do not track year-to-year inconsistencies in the presentation, categorization, or naming of existing data points.

Congressional District Tabulation Specifics

Location

The IRS maintains a dedicated web page with congressional district data at https://www.irs.gov/statistics/soi-tax-stats-data-by-congressional-district.

Publication Schedule, Format, and Years Available

Quick Reference Chart:

Statistics on individual income, deductions, and credits are compiled annually by congressional district. They are usually released around the end of February in the third year following the taxable year. For example, 2021 tabulations were released February 29, 2024, using district boundaries for the 117^th Congress (2021-2023).²⁵

Data may be downloaded (1) by individual state (Excel files), (2) as a single comprehensive file (either Excel or CSV), or (3) as a ZIP file containing all individual state Excel files, documentation, and the CSV files. These tabulations are available beginning with tax year 2017.

Tabulation-Specific Methodology and Limitations

The IRS determines a taxpayer's congressional district based on the ZIP code listed on the return.²⁶ Seven states (Alaska, Delaware, Montana, North Dakota, South Dakota, Vermont, and Wyoming) and the District of Columbia each have one congressional district, so the ZIP code matching procedures are not performed on these states.²⁷

Congressional district data cover the 50 states and the District of Columbia. Congressional district boundaries are based on the Congress in session during the tax year in question. As a result of changes to these boundaries across Congresses, data for specific numbered districts may not be comparable over time.

The data are tabulated by congressional district and AGI band. The highest-income AGI band for congressional district tabulations is "$500,000 or more."²⁸

State Tabulation Specifics (Individual Income Tax)

There are multiple datasets available for state totals of individual tax statistics: (1) comprehensive individual income and tax data (Historic Table 2), (2) calendar year return projections by state (Publication 6149), and (3) AGI percentile by state. Additionally, there may be state totals available in local area tabulations (see "County, Metropolitan, and Micropolitan Area" below) or other publications.

State totals are not comparable across IRS products due to sampling and data protection processes. This potentially produces different results.

Location

Locations vary, as listed under each publication below.

Publication Schedule, Format, and Years Available

Quick Reference Chart:

Historic Table 2

https://www.irs.gov/statistics/soi-tax-stats-historic-table-2

Comprehensive individual income tax state data (Historic Table 2) are available for individual states, the District of Columbia, Puerto Rico, "other areas," and nationally or as a combined file containing data for all states. Annual data tabulations are available beginning with tax year 1996.

State tabulation data in Historic Table 2 use all IRS-listed AGI bands shown in Table 2. Table 3 lists the source forms and lines for the included individual income tax data.

Publication 6149 (Multiyear Projections)

https://www.irs.gov/statistics/soi-tax-stats-calendar-year-projections-publication-6149

Every year the IRS releases Publication 6149, a report containing multiyear projections of the number of tax return filings expected for about 50 individual, business, and tax-exempt return types.²⁹ Projections are typically published in mid- to late December of the tax year in question (e.g., the projection for tax years 2025-2032 was published in December 2025). Publication 6149 data tabulations are available beginning with tax year 2005.

AGI Percentile Data

https://www.irs.gov/statistics/soi-tax-stats-adjusted-gross-income-agi-percentile-data-by-state

AGI percentile data includes annual tabulations of the total number of returns with positive AGIs within the top 1, 5, 10, 25, 50, and 75 percentiles of the AGI distribution for the United States, each state, and the District of Columbia.³⁰ Table 1 includes the total returns in each percentile along with the AGI floor, total AGI, total income tax, average tax rate, and percentage shares of AGI and income tax for each percentile category. Table 2 includes the total returns in each percentile along with the number of returns and total amount of particular sources of income for each percentile.

AGI percentile data tabulations are available for all states and the District of Columbia for tax years 2013 to present.³¹ Data tables are typically published in late February of the third year after the tax year tabulated (e.g., 2022 tabulations were released in February 2025).

Tabulation-Specific Methodology and Limitations

The IRS uses the state codes as they are listed on the returns. The SOI division does not attempt to correct any listed state code.³² Each publication categorizes international addresses and addresses in U.S. territories differently. For example, Historical Table 2 includes tabulations for Puerto Rico and "Other Areas," Publication 6149 includes tabulations only for "International," and the AGI percentile tabulations exclude those addresses altogether.³³

State Tabulation Specifics (Estate Tax)

Location

Federal estate tax data for specific states are available at https://www.irs.gov/statistics/soi-tax-stats-estate-tax-statistics.

Publication Schedule, Format, and Years Available

Quick Reference Chart:

Filing Year Tabulations

Estate tax data "Table 2: Selected Tax Computation Items" and "Table 3: Charitable Bequests" are tabulated by state of residence from returns filed during a single calendar year (filing year tables) regardless of the decedent's date of death.³⁴ This annual release has a delay of two years from the date of returns. For example, data tabulations from returns filed during 2022 were released in September 2024. Table 2 data tabulations are available from tax year 1995 and Table 3 from tax year 2010.

Year-of-Death Tabulations

Every three years, the IRS releases year-of-death estate tax data tabulations by state of residence as "Table 3: Estate Tax Returns, Year of Death by State of Residence." The release in January 2023 was for data from estate tax returns for individuals who passed away in 2019. Another release is expected in 2026 for 2022 year-of-death filings. This table is available for approximately every three calendar years (intervals are inconsistent) from calendar year 1989.

Some files are titled incorrectly and thus hosted in the wrong location on the year-of-death filings web page. Some data classified by state of residence ("Table 3") are erroneously titled as "Table 4" (within the Excel file) and thus the files are linked on the website under "Table 4," which should contain data classified by sex and marital status of decedent, even though the files contain data classified by state of residence. For those affected files, the tabulation linked under the "Table 3" heading is classified by sex and marital status instead of by state of residence. Therefore, if the file linked under "Table 3" contains the incorrect classification, check the corresponding file under the "Table 4" heading for the file containing data classified by state of residence.

Tabulation-Specific Methodology and Limitations

Estate tax tabulations are based on returns sampled during processing and before audit examinations.³⁵ All returns exceeding the estate tax threshold are included in the sample (sample selection rate of 100%).³⁶ For the triennial year-of-death data, the sample is weighted to account for the less than 1% of estate returns not yet filed at the end of the three-year period for the sampled calendar year (the first year of the three-year period).³⁷

Tabulations include a location for the District of Columbia and an "Other areas" category that encompasses U.S. territories, U.S. citizens living abroad at their time of deaths, and a small number of returns for which states of residence were unknown.³⁸

County, Metropolitan, and Micropolitan Area Tabulation Specifics

Location

Federal income tax data by county, metropolitan area, and micropolitan area are available at https://www.irs.gov/statistics/soi-tax-stats-county-data.

Publication Schedule, Format, and Years Available

Quick Reference Chart:

County income data tabulations are based upon the location of the address reported on the individual tax return filed. These tabulations are compiled annually and are usually released around the end of February in the third year following the taxable year (e.g., 2021 tabulations were released February 29, 2024).

Metropolitan and micropolitan statistical area tabulations are created for urban core populations of 50,000 or more (metropolitan areas) and for areas with populations of at least 10,000 but less than 50,000 (micropolitan areas).³⁹ Tabulations are categorized by AGI. The highest AGI band for county-level data is $200,000 or more.⁴⁰

Annual tabulations are available beginning from tax year 1989, although the format changed beginning with the tax year 2011 report.

See Table 3 for a listing of included individual income tax data by IRS form and line.

County data tabulations are available as (1) Excel files for each state, (2) a single file containing information from all states but excluding classification by AGI, (3) a CSV file containing information for all states—either with or without AGI classification—and (4) a ZIP file including documentation and all the above-mentioned formats. Metropolitan and micropolitan statistical area data tabulations are available as a single CSV file.

Tabulation-Specific Methodology and Limitations

Geographic location is determined using nine-digit ZIP codes as listed on tax returns.⁴¹ The IRS does not correct any erroneous ZIP code information.⁴² Returns with ZIP codes that do not match the states listed and returns lacking ZIP codes are excluded.⁴³

Metropolitan and micropolitan statistical areas, also known as core based statistical areas, may cross county geographic boundaries.⁴⁴

Tax returns filed using APO and FPO addresses, foreign addresses, and addresses in Puerto Rico, Guam, the U.S. Virgin Islands, American Samoa, the Marshall Islands, the Northern Marianas, and Palau are excluded from county, metropolitan, and micropolitan tabulations.⁴⁵

Income and tax items with fewer than 20 returns for a county are excluded.⁴⁶

ZIP Code Area Tabulation Specifics

Location

Federal income tax data by ZIP code are available at https://www.irs.gov/statistics/soi-tax-stats-individual-income-tax-statistics-zip-code-data-soi.

Publication Schedule, Format, and Years Available

Quick Reference Chart:

Tabulations are compiled annually by ZIP code and are usually published around the end of February in the third year following the taxable year (e.g., 2021 data tabulations were released February 27, 2024).

Data are collected from individual income tax returns and include the number of returns, number of personal exemptions, AGI, wages and salaries, certain dividends, and interest received. Tabulations are available every year beginning with tax year 2004, although individual select years may be available beginning with tax year 1998. Tabulations are available as individual state Excel files or as a single CSV file with or without AGI classifications. A ZIP file is also available containing the state Excel files, the CSV files, and documentation.

See Table 3 for a listing of included data by IRS form and line.

Tabulation-Specific Methodology and Limitations

Tax returns filed using APO and FPO addresses; foreign addresses; and addresses in Puerto Rico, Guam, the U.S. Virgin Islands, American Samoa, the Marshall Islands, the Northern Marianas, and Palau are excluded.⁴⁷ Tax returns without ZIP codes and returns with ZIP codes that do not match the returns' listed states are excluded.⁴⁸

ZIP codes with fewer than 100 returns and ZIP codes identified as single buildings or nonresidential are categorized as "other."⁴⁹ Income and tax items with fewer than 20 returns within a ZIP code are excluded.⁵⁰

U.S. Population Migration Data, by State and by County

Location

Data on taxpayer address changes, as determined using the addresses listed on IRS returns, are available at https://www.irs.gov/statistics/soi-tax-stats-migration-data.

Publication Schedule, Format, and Years Available

Quick Reference Chart:

The IRS publishes inflow and outflow migration data by county and by state. Such data include the total number of returns filed, the total number of individuals in tax units in the area, and total AGI.

Tabulation-Specific Methodology and Limitations

Migration data are based on year-to-year address changes reported on individual tax returns.⁵¹ The number of returns is used to approximate the number of households that migrated, while the number of personal exemptions claimed is used to approximate the number of individuals who migrated.⁵² Tabulations are based upon returns filed prior to late September each year.⁵³ Returns filed after the cutoff are not included.⁵⁴ Total migration numbers will not match totals reported in other products due to the truncated collection period used.

Counts less than 20 at the county level are excluded. (Prior to 2019, a count less than 20 at the county level was included with a similar category in another county within the same state.⁵⁵) Counts less than 10 at the state level are excluded.⁵⁶ Because records may be excluded at the county level that were included at the state level, the sum of all county totals for a state may not equal the listed state total. Returns without ZIP codes or with ZIP codes that do not match the state codes listed on the returns are excluded.⁵⁷ A return for which the taxpayer is claimed as a dependent on another tax return in the second comparison year is excluded. This could include, for example, elderly parents with caretaking needs who move in with their adult children. On the other hand, a return for which the taxpayer is claimed as a dependent in the first comparison year and then filed as a non-dependent in the second year is included. One example of this might be an individual who is 17 years old in the first year but files his or her own tax return as an 18-year-old adult in the second year.⁵⁸

Foreign returns; APO and FPO addresses; and addresses in Puerto Rico, Guam, the U.S. Virgin Islands, American Samoa, the Marshall Islands, the Northern Marianas, and Palau are included in migration counts under a designation of "foreign."

Footnotes