Based off the ZIP Code associated with your question, I think you live in California. Unfortunately, California does not offer a state income tax deduction for contributions to 529 college savings plans. Many states do allow you to take a state income tax deduction, so if my assumption is incorrect, you may be able to deduct a contribution. One advantage of the 529 plan is that you have no income limitations, and the recipient of the account does not have to be below a certain age. As a result, this funding strategy works quite well for graduate school.
Additionally, you would need to be careful with the amount you funded into the plan. Although 529 plans do not have contribution limits, you would give your son money higher than the gift tax exclusion amount with a contribution of $75,000 unless you structured it carefully. In 2017, you are allowed to gift $14,000 to anyone you want without having to file a gift tax return. If you are married, your spouse can do the same thing, but you would then need to file a gift tax return indicating that you both gave to the same person. Although this gift splitting does not result in gift tax, it is an additional step and can be a headache. 529 plans allow an unusual bulk funding of five years of gift tax exclusion in one year. This would result in a maximum gift of $70,000 given by one of you in a single year without needing to split the gift. The $70,000 is, however, still lower than the amount you wanted to fund. To get to $75,000, you would have to trigger the gift splitting mechanism. Additionally, you should know that this is all you can give your son for five years without triggering gift tax issues, and if you should die during the five year period, some of the money would need to be recharacterized.
The following IRS link might be useful to you. You can click on it, or type in the URL https://www.irs.gov/businesses/small-businesses-self-employed/frequently-asked-questions-on-gift-taxes
Remember, though, if you live in California, this is a lot of information you can’t use, as you aren’t allowed to deduct contributions to 529 plans at all.
Best of luck! Peggy