My son was living with me in all 2018 rent-free, can I deduct potential loss of room rent on my tax return? For the tax purposes I cannot claim his as a dependent.

[MichaelL1]

Unfortunately this is considered a personal non-deductible personal expense.

I have children live me for various times and like the thought process you have.

[MichaelL1]

If I did not fully answer your question, please give me additional detail so I can help.

I cannot tell you to deduct something when it is clearly not deductible.

[macuser_22]

Losses of income that you did not previously pay tax on can never be deducted no matter what the circumstances

You just have less income to pay tax on.    A tax "deduction" is just getting the tax back that you previously paid on the income.   Since you never received the income in the first place, you did not pay any tax to deduct.

A personal gift is never delectable anyway.  It is your discussion not to charge rent.

[victoria-gonchar]

my friend had a similar situation with her mom living in my friends house rent-free and CPA was applying lost rent rule/concept? to my friend's tax return. What is lost rent and how it is used for tax purposes

[MichaelL1]

I am a CPA also and there are rules when you rent at less than FMV, however there is no lost rent rule/concept and I would be shocked to see a CPA try that.

The less than FMV rent rule allows expenses to be deducted up to the rent paid, which in this case is $0