Ohio requires the use of the four-digit code when filing your tax return. Most W2's list this code in box 20 for you, but if yours did not, then you can use the tools below to help locate the number.
Lookup tool by address or zip code -
https://thefinder.tax.ohio.gov/streamlinesalestaxweb/default_schooldistrict.aspx
List by County -
https://www.tax.ohio.gov/Portals/0/tax_analysis/tax_data_series/school_district_data/SDIT_LIST.pdf
