Aesthetic salon owner Fumie Takeuchi splurged 3 million yen (S$37,000) on jewellery at one go earlier this month, after a saleswoman gently reminded her that the sales tax was going up on April 1.
"I had long been eyeing a certain black diamond ring but hesitated because it was rather expensive," said Mrs Takeuchi, 57.
"But the other day, when the saleswoman gave me a nudge by pointing out that the tax hike was imminent, I succumbed."
From April 1, the goods and services tax (GST) will be raised from 5 to 8 per cent.
Besides the black diamond ring, Mrs Takeuchi walked out of the store with a pendant, a sapphire ring and a pearl necklace, the last three items bought largely on impulse, she said.
Across Japan, consumers who want to avoid paying the higher sales tax have been rushing out to buy big-ticket items or stock up on daily essentials.
The Japan Department Stores Association said its members in the Tokyo area reported that sales went up by 15 per cent as of mid-March.
At Yamada Denki, Japan's largest home electronics discounter, sales soared 27 per cent last month and are expected to be even higher this month, thanks to a surge in purchases of air-conditioners, television sets and fridges.