There is much discussion about tax residency. If you are a resident and / or citizen of the US and Italy, Article 4 of the tax treaty between the US and Italy is applicable, Here is the link.
https://www.irs.gov/pub/irs-trty/italy.pdf. Also, here is the link to being a tax resident in the US. https://www.oecd.org/tax/automatic-exchange/crs-implementation-and-assistance/tax-residency/United-States-Tax-Residency.pdf. Residency and domicile, along with tax residency for state purposes (and sometimes Federal purposes) are governed by State laws. Tax status is highly fact sensitive.
If one is a resident of the US and Italy tax status is governed by the treaty and 183 days is not an acid test. Always best to ask an expert and even better, to ask an expert to help structure before taking action. I am a dual resident of Italy and the US for 4 years now and am governed by the treaty.
https://www.irs.gov/pub/irs-trty/italy.pdf. Also, here is the link to being a tax resident in the US. https://www.oecd.org/tax/automatic-exchange/crs-implementation-and-assistance/tax-residency/United-States-Tax-Residency.pdf. Residency and domicile, along with tax residency for state purposes (and sometimes Federal purposes) are governed by State laws. Tax status is highly fact sensitive.
If one is a resident of the US and Italy tax status is governed by the treaty and 183 days is not an acid test. Always best to ask an expert and even better, to ask an expert to help structure before taking action. I am a dual resident of Italy and the US for 4 years now and am governed by the treaty.