Can I cash in a ee treasury bond and put all of it into 529 plan?
Yes, you can likely cash in a Series EE Treasury bond and deposit the proceeds into a 529 plan. This can be done without paying federal tax on the bond's interest if the funds are used for qualified education expenses.
Regarding gift tax exemption, contributions to a 529 plan are considered gifts and are subject to federal gift tax rules.
However, you can use the annual gift tax exclusion amount ($18,000 per recipient in 2024) or spread larger contributions over five years to avoid gift tax.