My husband's parents signed their house over to him. How do I claim that?

[lindamaloo--]

They are still living in it and we don't pay anything for upkeep. (taxes, household expenses etc.)

[xmasbaby0]

You do not "claim" anything for that.   Gifts that you receive are not reported on a tax return.  And since you are not paying anything---like mortgage interest or property tax, you have nothing to enter about the house on an income tax return.

However, your in-laws need to complete a Form 709 Gift Tax form.

Gifts given to family members, friends or other individuals are not deductible.   Gifts received are not taxable to the person who received the gift, and are not entered on a tax return.

If your gift exceeds the yearly limit ($17,000 per individual)  imposed by the gift tax rules, then you will need to complete a Form 709 gift tax form and send it to the IRS, although it is very unlikely that you will owe any tax. 

TurboTax does not support Form 709.  It is not an income tax form and would not be included as part of an income tax return.

Here is a link to the form:

https://www.irs.gov/pub/irs-pdf/f709.pdf

https://turbotax.intuit.com/tax-tips/estates/the-gift-tax-made-simple/L5tGWVC8N

[Hal_Al]

"Gift Tax return" is somewhat of a misnomer.  Even though a gift tax return may be required, very few people ever actually pay federal gift tax. The purpose of the gift tax return is usually only to document a reduction in the allowable estate tax exemption.
See https://turbotax.intuit.com/tax-tools/tax-tips/Tax-Planning-and-Checklists/The-Gift-Tax-Made-Simple/...   

[Mike9241]

I assume this was done without professional advice. extremely inefficient from a tax standpoint. he gets their tax basis so if he sells the gain is the difference between the sales price net of selling costs and the parent's tax basis + the cost of any improvements he makes. There will be no home sale exclusion unless he (and you) lives in it for a least two years before the sale as his (your) principal residence. He may also have the right to evict his parents so the property can be sold.  It would have been much better if the parents had created a life estate that would allow them to live there until they die. your husband would get a step-up in basis which would reduce any taxable gain.   

[xmasbaby0]

And....of course there is also the concern that if the parents who "signed over" their house are anticipating the possibility of going into a nursing home in the next several years and getting on Medicaid, there is a five year clawback on any assets or money they gave away.  An elder law attorney should have been consulted before this took place.