WASHINGTON (Reuters) -Millions of U.S. retirees and other Social Security recipients will have to wait for a while to learn how big their checks will be in 2026 as the ongoing partial government shutdown is set to delay the release of September's consumer inflation data.

The Social Security Administration would have used the Consumer Price Index for Urban Wage Earners and Clerical Workers data from the third quarter of 2024 to the third quarter of 2025 to determine the annual cost-of-living adjustment for Social Security and Supplemental Security Income benefits for next year. 

The programs benefit older Americans who have retired from their jobs as well as the disabled and certain widows, widowers and children. The COLA announcement - a widely anticipated event each October among the households relying on those payments - is typically made shortly after the Bureau of Labor Statistics releases September's CPI report. 

But the shutdown, triggered by a lapse in government funding amid a political standoff between Republicans and Democrats in Washington, has halted the collection and publication of key economic data, including the closely watched employment report for September that was scheduled for release last Friday.

September's CPI report is due October 15. Even if Congress reaches a deal to reopen the government, a delay is still likely due to the time required for BLS to process the data. 

In 2025, more than 72.5 million Social Security and SSI beneficiaries received a 2.5% COLA increase. 

The Senior Citizens League, one of the nation's biggest seniors groups, last month projected a 2.7% COLA raise in 2026, which would lift the average monthly benefit for retirees by $54 to $2,062 from $2,008.

Consumer inflation accelerated in August as businesses passed on higher costs from President Donald Trump's sweeping tariffs. Economists expect prices to increase further, arguing the full inflationary effects of tariffs are still to be felt.