Tax class III applies to married/partnered employees upon application if both spouses/life partners reside in Germany, do not live permanently separated, and the employee's spouse/life partner does not receive wages or receives wages and is placed in tax class V. Widowed employees are only in tax class III for the calendar year 2023 if the spouse/life partner died after December 31, 2021, both spouses/life partners lived in Germany on the date of death and did not live permanently separated.
In cases of marriage, you and your spouse will initially be automatically assigned tax class IV in the new electronic ELStAM (Elektronische LohnSteuerAbzugsMerkmale) procedure. Consequently, you will be assigned tax class IV (and not III) even if your spouse is not employed. If you want tax class III to be taken into account, you must apply for this on the official form Antrag auf Steuerklassenwechsel bei Ehegatten/Lebenspartnern.-Sonstiges- Suchen - Titel: Antrag auf Steuerklassenwechsel bei Ehegatten/Lebenspartnern. An application is possible electronically in the Elster portal My ELSTER.