Open data
Michigan data downloads
These are the datasets behind Michigan Porch's calculators, as free JSON files. Use them in apps, spreadsheets, articles, or research. Each file names its official source and its vintage — the report and year the numbers come from — inside the file itself. The license and the credit line ride along too, so a copy that travels still says where it came from.
File format
One JSON object per dataset
The rows sit under the data key. The rest of the
object describes the rows: source,
vintage,
lastUpdated,
fields,
rowCount,
license,
attribution, and
citeAs. The endpoints are versioned under
/data/v1/ and allow cross-origin requests, so a
script or page on another site can fetch them directly.
Dataset
Michigan property tax millage rates
Total property tax millage rates for Michigan cities and townships, by school district. One mill is $1 of tax per $1,000 of Taxable Value. The rows are parsed from the Michigan Treasury 2025 Total Property Tax Rates report.
One row per city or township and school-district combination, covering all 83 counties. This file powers the Michigan Homebuyer Tax Calculator.
- Rows
- 3,574
- Vintage
- 2025 Michigan Treasury Total Property Tax Rates
- Last updated
- 2026-05-28
License and citation
Licensed CC BY 4.0. Reuse is welcome, including commercial reuse. Keep this credit line with the data:
Data: Michigan Porch (michiganporch.com) — CC BY 4.0
For a formal reference, cite the file like this:
Michigan Porch, "Michigan property tax millage rates" (2025 Michigan Treasury Total Property Tax Rates). https://michiganporch.com/data/v1/millage-rates.json. CC BY 4.0. Underlying figures: Michigan Treasury 2025 Total Property Tax Rates report.
Field dictionary
| Field | Type | Meaning |
|---|---|---|
| county | string | Michigan county name. |
| municipality | string | Local taxing unit name as printed in the Treasury report, for example "Alcona Twp". |
| unitCode | string | Six-digit Michigan Treasury code for the local unit of government. |
| schoolDistrict | string | School district name as printed in the Treasury report (uppercase, sometimes shortened). Some entries carry a tax-area or village suffix. |
| preMillage | number | Total millage, in mills, for a home with a Principal Residence Exemption (PRE). Does not include ad valorem special-assessment mills. |
| nonHomesteadMillage | number | Total millage, in mills, for non-homestead property — property without a PRE, such as rentals and second homes. Does not include ad valorem special-assessment mills. |
| preMillageWithSpecial | number | PRE millage including any ad valorem special-assessment mills the report lists for the unit. |
| nonHomesteadMillageWithSpecial | number | Non-homestead millage including any ad valorem special-assessment mills the report lists for the unit. |
| commercialPersonalMillage | number | Total millage the report lists for commercial personal property, in mills. |
| industrialPersonalMillage | number | Total millage the report lists for industrial personal property, in mills. |
| displayName | string | Reader-friendly unit name used on Michigan Porch, for example "Alcona Township". |
| type | string | Local unit type: "city", "township", or "village". |
| slug | string | Michigan Porch place identifier. The matching page is michiganporch.com/places/{slug}/. |
Dataset
Michigan city income tax rates
The 24 Michigan cities that levy a city income tax, with resident and nonresident rates as decimals. Most cities use 1% for residents and 0.5% for nonresidents; Detroit, Grand Rapids, Highland Park, and Saginaw use higher rates.
One row per taxing city. This file powers the city income tax checker.
- Rows
- 24
- Vintage
- Michigan Treasury city-income-tax list and 2025 taxpayer manual
- Last updated
- 2026-05-29
License and citation
Licensed CC BY 4.0. Reuse is welcome, including commercial reuse. Keep this credit line with the data:
Data: Michigan Porch (michiganporch.com) — CC BY 4.0
For a formal reference, cite the file like this:
Michigan Porch, "Michigan city income tax rates" (Michigan Treasury city-income-tax list and 2025 taxpayer manual). https://michiganporch.com/data/v1/city-income-tax.json. CC BY 4.0. Underlying figures: Michigan Treasury list of cities that impose an income tax.
Field dictionary
| Field | Type | Meaning |
|---|---|---|
| city | string | City name. City income tax applies inside the legal city boundary, not the wider mailing area that shares the city's name. |
| residentRate | number | Rate for people who live in the city, as a decimal (0.01 = 1%). |
| nonresidentRate | number | Rate for people who live elsewhere but earn wages inside the city, as a decimal (0.005 = 0.5%). It applies to the in-city wages. |
Dataset
Michigan recurring deadlines
The recurring dates that matter to Michigan homeowners, homebuyers, movers, and the outdoors crowd — tax bills, PRE deadlines, the March Board of Review, license years, and season opens. The dates are the same for everyone statewide; each row links the page that explains it.
One row per recurring statewide date. This file powers the homepage calendar and the .ics feed.
- Rows
- 18
- Vintage
- Michigan statutes and 2026 agency pages, as cited per row
- Last updated
- 2026-07-08
License and citation
Licensed CC BY 4.0. Reuse is welcome, including commercial reuse. Keep this credit line with the data:
Data: Michigan Porch (michiganporch.com) — CC BY 4.0
For a formal reference, cite the file like this:
Michigan Porch, "Michigan recurring deadlines" (Michigan statutes and 2026 agency pages, as cited per row). https://michiganporch.com/data/v1/deadlines.json. CC BY 4.0. Underlying figures: Official sources linked per row (Michigan Treasury, DNR, legislature.mi.gov).
Field dictionary
| Field | Type | Meaning |
|---|---|---|
| slug | string | Stable event identifier. |
| label | string | Event name. |
| month | number | Month of the year, 1–12. |
| day | number | Day of month for fixed statutory or season dates. Absent when the date shifts year to year. |
| window | string | Display text for events without a fixed day, for example "The last Saturday in April". |
| audience | string | Who the date matters to: "buyer", "owner", "mover", or "outdoors". |
| blurb | string | One or two plain sentences on what the date means. |
| url | string | The michiganporch.com page that explains the date. |
| officialLabel | string | Name of the official source, when one is linked. |
| officialUrl | string | Official source URL, when one is linked. |
License
License and attribution
Both files are licensed Creative Commons Attribution 4.0 (CC BY 4.0). You can copy, reshape, and republish the data — in a product, a story, a model, or a class project — as long as the credit line stays with it.
The State of Michigan publishes the underlying figures. The license covers Michigan Porch's cleaned, combined, and documented files. When a number is load-bearing for your work, check it against the official source linked on each dataset — that source decides.
Sources and review
The official sources
Michigan Porch parses and rechecks official state publications. These are the documents behind the two files.
- Last reviewed
- June 8, 2026
- Michigan Treasury millage-rate reports for official local millage-rate reports.
- 2025 Total Property Tax Rates PDF for source file parsed into the statewide Michigan Porch millage data.
- State of Michigan property tax estimator for official parcel-oriented property tax estimate.
- Michigan Treasury list of cities that impose income tax for current list of city income tax authorities.
- Michigan Treasury Taxpayer Assistance Manual for standard and alternate city tax rates.
- Michigan City Income Tax Act for state law behind city income tax.
Use this carefully: These files are planning aids. The local assessor, city treasurer, or Michigan Treasury controls the official number for a specific parcel, taxpayer, or year.
Next steps
Where to next
The tools these files power, plus the rest of the toolbox.
Calculator
Michigan Homebuyer Tax Calculator
Estimate a buyer's first full-year property tax bill after uncapping, using the millage data above.
Open the calculator →Checker
City Income Tax Checker
Check whether living or working in a Michigan city adds a local income tax to your paycheck.
Open the checker →Tools
Browse all tools
See every Michigan Porch calculator and guide that is ready now.
Open tools →Page feedback
See something wrong or unclear?
Send a note about this page. The page address will be included automatically.
Page feedback
Send a note
The page you're on will be included automatically.