Hi there. You as recipients do not have to pay tax on a gift, however your in-laws will need to fill out a gift tax return or returns if one or both of them gifts one or more individuals more than $12,000 per year. As a couple, they can each gift you and your spouse 12,000, resulting in a total gift of $48,000, without having to file a gift tax return. However, if the amount to one individual goes above 12,000, or they elect gift-splitting (splitting one gift between donor spouses), they will need to file gift tax return(s). Most likely they will not owe any gift tax if they have n ot reached the lifetime limit of 1 million dollars in taxable gifts. See below for more information about the gift tax rules:
An individual can give a gift of up to $12,000 in one year (2006) to another individual before any gift tax implications kick in. If you give above $12,000 to any one individual, you must file a gift tax return. The $12,000 is your gift tax exclusion. There is a separate 12,000 exclusion to each person that you make a gift to. Any amount over this is applied to your lifetime limitation of 1 million dollars.
Up to 1 million dollars, there is no gift tax due, because of something called the Unified Credit. After the 1 million dollar lifetime exclusion gets used up, gift tax percentage ranges from 18-46%.
Keep in mind that certain gifts are not subject to gift tax, such as to political organizations, between US resident spouses, and gifts that are made for directly to a school or medical facility or professional for tuition or medical expenses paid on behalf of another.
Also to note, any unified credit used for gift tax purposes will reduce the amount of credit that can be used for estate tax purposes.