Less Estate Tax Planning May Be Better for Longer-Living Rich

Terms like “reverse estate planning” and “backdoor spouse planning” are becoming part of the new lexicon for estate tax advisers as millionaire clients live into their late 80s and beyond.

A central tenet of estate tax planning involves giving up control of assets, to remove them from an estate and lower the eventual tax bill. But if people plan too aggressively, too early—and live longer than they were expecting—they risk giving away too much to beneficiaries and forfeiting the lifestyle they’ve grown accustomed to in later years.

It gives rise to situations where “the kids are ...