If you give a non-spouse a gift valued more than the annual exclusion amount, you could be subject to a gift tax.
For 2019, the annual federal gift tax exclusion amount for gifts to a non-spouse is $15,000 per person, per year.
If you are married, you and your spouse may give up to $30,000, per person, per year, free from federal gift tax.
Although there are no immediate tax concerns for the recipient of a gift because federal gift tax is imposed upon the donor, the recipient could be liable for capital gains tax in the future. Highly appreciated gifts such as real estate or stocks will render the recipient liable for capital gains tax when he or she decides to sell the gift at a later date.
The general rule from the IRS is that the recipient’s basis in the gifted property is the same as the basis of the donor. The IRS provides this example: If you were given stock that the donor had purchased for $10 per share (which was also his/her basis) and you later sold it for $100 per share, you would pay tax on a gain of $90 per share.
Source: www.irs.gov