Investors & landlords

Interesting idea. TLDR; you are on iffy grounds unless your son spends more time in the condo than he does elsewhere or has very significant ties to CA and a clearly demonstrable intent to live in CA after school. Even then the fuzzy tests would not seem to be in your favor.

1. The address on the tax form has almost no weight in the determination of residence. It might be a factor, but it would be a small one. (See below.)

2. You will have to file a federal gift tax return for the gift at the fair-market value as of the transfer. (Form 709). No gift tax will be due if the condo value and the sum of your prior gifts is < about $11M. This will reduce  your federal estate "free transfer amount." That may not matter because it is so large (about $11M scheduled to go back down to $5M in a few years.) You son's basis for gain will be the same as yours. He's basis for loss will be the FMV at date of transfer.

3. Here are the rules for what your primary residence is. You might need to read any cases interpreting them, but it gives you the idea. You are on iffy grounds. These quotes are from 26 C.F.R. 1-1.121-1, the Treasury Dept regulations implementing the section 121 exclusion. https://www.law.cornell.edu/cfr/text/26/1.121-1

(b) Residence -

(1) In general. Whether property is used by the taxpayer as the taxpayer's residence depends upon all the facts and circumstances. A property used by the taxpayer as the taxpayer's residence may include a houseboat, a house trailer, or the house or apartment that the taxpayer is entitled to occupy as a tenant-stockholder in a cooperative housing corporation (as those terms are defined in section 216(b)(1) and (2)). Property used by the taxpayer as the taxpayer's residence does not include personal property that is not a fixture under local law.

(2) 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. If a taxpayer alternates between 2 properties, using each as a residence for successive periods of time, the property that the taxpayer uses a majority of the time during the year ordinarily will be considered the taxpayer's principal residence. In addition to the taxpayer's use of the property, relevant factors in determining a taxpayer's principal residence, include, but are not limited to -

(i) The taxpayer's place of employment;

(ii) The principal place of abode of the taxpayer's family members;

(iii) The address listed on the taxpayer's federal and state tax returns, driver's license, automobile registration, and voter registration card;

(iv) The taxpayer's mailing address for bills and correspondence;

(v) The location of the taxpayer's banks; and

(vi) The location of religious organizations and recreational clubs with which the taxpayer is affiliated.