Do I still need life insurance once my mortgage is paid off and kids are grown?

Often no, and that is by design. Term life exists to cover the years when others depend on your income, so once the mortgage is gone, the kids are self-supporting, and your retirement savings can carry your spouse, the need frequently disappears. That is the whole reason term is cheaper than permanent coverage. There are exceptions: you might keep some coverage if a spouse relies on your pension or Social Security that would shrink at your death, if you have a special-needs dependent, or if you face an estate-tax liability. Before dropping a policy, confirm your survivors would be financially secure. If the answer is yes, letting term lapse and investing the former premium is usually the smarter move.