If a non relative gives someone a house worth $550,000, is there a gift tax incurred? Thanks

[xmasbaby0]

Yes.    The person who received the gift does not have to report the gift---gifts are not taxable for the recipient of a gift.   But the person who GAVE the gift must complete a gift tax Form 709 if the gift to one person was more than $15,000 in one year.   That does not mean tax will be owed----but the gift must be reported against a lifetime gift limit amount.

GIFTS

Money that you receive as a gift is not taxable income to you, and you do not need to report it on your income tax return.  Money that you gave as a gift to someone else is not deductible for your taxes.

Turbo Tax does not support the gift tax form 709, but here is a link:

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

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

https://www.forbes.com/sites/ashleaebeling/2017/10/19/irs-announces-2018-estate-and-gift-tax-limits-...

[Critter-3]

What is important to the receiver is the donors basis and the current fair market value.

https://ttlc.intuit.com/community/investments/help/how-do-i-determine-the-cost-basis-of-stock-i-rece....

[Hal_Al]

"Gift Tax" 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/....