When can a grandchild cash Savings Bonds?

I have been purchasing bonds for my grandchildren since they were born. The bonds are in their names and social security numbers. At what age can they start cashing them in? Tom's response The bonds can be redeemed as soon as the bonds are a year old. A child who is old enough to sign his or her name can go to a financial institution with an adult and sign the bonds. If a child isn't old enough to sign, his or her parents can sign for the child. If the child is under 14, the interest income has to be declared on the parent's return and taxed at the parent's tax rate. If older, the child can declare it on his or her own return.