PRINCIPAL RESIDENCE. In the case of a taxpayer using more than one property as a residence, whether property is used by the taxpayer as the taxpayer's principal residence depends upon all the facts and circumstances.
The principal residence is the home that you physically occupied and personally used the most during the five years preceding the sale of the property. Moving furniture and personal belongings into a residence does not qualify as use.
If the homeowner has two houses and uses each as a residence for successive periods of time (such as alternating between Florida in the winter and Washington during the rest of the year), the property that the homeowner uses most of the year usually will be considered the principal residence.
For a mortgage interest deduction, your main home and second or vacation home will qualify.
