About 1 in 10 Social Security recipients will receive a double December payment, with their second monthly check arriving on December 29. 

That's because of a quirk in the system for the Social Security Administration's Supplemental Security Income (SSI) program, which provides support for disabled people and older Americans with low incomes. 

Typically, SSI recipients receive their payments on the first of each month, which means the program's 7.5 million enrollees received their December payment on December 1. But because January 1 is a holiday, SSI recipients are getting their January check on the last weekday before the New Year, with deposits landing on December 29. 

SSI recipients will get another bonus with their December 29 payment: Their 2024 cost-of-living adjustment will be included in the check.

The 2024 cost-of-living adjustment, or COLA, is set for a 3.2% increase, marking the smallest increase in three years. That's because the COLA is based on the inflation rate, which has been rapidly cooling in the face of the Federal Reserve's regime of interest rate hikes. 

The average SSI check will rise to $943 per month in 2024l, up from $914 per month in 2023, according to the Social Security Administration.

Social Security payment schedule 2024

While the new COLA increase takes effect with December benefits, those payments will reach most recipients in January, with the exception of SSI recipients, according to the Social Security Administration. 

With the increase, the average retirement benefit check will go up about $60 per month, rising to $1,907 from this year's $1,848, the agency said.

Here is the payment schedule for the first 2024 checks reflecting the new COLA.

• Dec. 29, 2023: The benefits hike for the nation's 7.5 million SSI recipients will begin on this day. Typically, SSI payments are issued on the first of each month, but because January 1 is a holiday, recipients will get their payments on the Friday before January 1. 
• Jan. 3, 2024: If you started claiming Social Security before May 1997 or if get both Social Security and SSI benefits, you'll get the new COLA in a Dec. 29, 2023 check and your Social Security payment on January 3.
• Jan. 10, 2024: If your birthday falls between the 1st to the the 10th day of your birth month, this is when you'll get your first benefit check with the new COLA. For instance, if your birthday is June 1, you'll get paid on this day.
• Jan. 17, 2024: If your birthday falls between the 11th to 20th day of your birth month, you'll get your higher payment on this day.
• Jan. 24, 2024: If your birthday falls between the 21st to 31st of your birth month, your benefit check will reflect the new COLA on this day.

In:
• Social Security

Aimee Picchi is the associate managing editor for CBS MoneyWatch, where she covers business and personal finance. She previously worked at Bloomberg News and has written for national news outlets including USA Today and Consumer Reports.