Shoko Iwasaki looked for years for a tax-free way to pass down a lifetime of savings to her grandson. Prime Minister Shinzo Abe has offered the 71-year-old an answer with a program now helping unlock pensioners' hoarded wealth.

"I'm so grateful for this tax measure, which enables me to hand over my money all at once," said Iwasaki, who lives alone in Ashiya, Hyogo Prefecture. She plans to endow ¥15 million for the education of her grandson under an initiative introduced this year exempting tax on lump-sum gifts to children for schooling expenses.

Potential transferable assets to the younger generation under the program that lasts through 2015 amount to ¥117 trillion, according to estimates by Goldman Sachs Group Inc. Gifts of just 10 percent of the total could see ¥4 trillion a year trickling down — an amount equivalent to 1.7 percent of annual consumer spending in the world's third-largest economy.