The tertiary index, which measures spending in the services sector, jumped 1.7% in April from March, the third rise in four months, the Ministry of Economy, Trade and Industry said, citing preliminary data.
The index stood at 110.4 last month, slightly below February's 110.7, which was the highest level since January 1988. That followed a 1.9% fall in March from the previous month.
Year-on-year, the index increased 1.3% in April after a 0.9% gain in March.
The services sector employs more than half of Japan's workforce, and spending on services such as retailing, dining and travel is closely tied to changes in income and consumer confidence.