What is a COLA?
Legislation enacted in 1973 provides for costofliving adjustments, or COLAs. With
COLAs, Social Security and Supplemental Security Income (SSI) benefits keep pace with
inflation. Latest COLA
The latest COLA is 2.8 percent for Social Security benefits and SSI payments.
Social Security benefits will increase by 2.8 percent beginning with the December
2018 benefits, which are payable in January 2019. Federal SSI payment levels
will also increase by 2.8 percent effective for payments made for January 2019.
Because the normal SSI payment date is the first of the month and January 1 is a
holiday, the SSI payments for January are always made at the end of the previous
December.
How is a COLA calculated?
The Social Security
Act specifies a formula for determining each COLA. According to the formula, COLAs
are based on increases in the Consumer Price Index for Urban Wage Earners and Clerical
Workers (CPIW). CPIWs are calculated on a monthly basis by the Bureau of Labor
Statistics.
A COLA effective for December of the current year is equal to the percentage increase
(if any) in the CPIW from the average for the third quarter of the current year to the average for the third quarter of the last year in which a COLA became effective. If there is an increase, it must be rounded to the nearest tenth of one percent. If there is no increase, or if the rounded increase is zero, there is no COLA for the year.
COLA Computation
The last year in which a COLA became effective was 2017. Therefore the law requires
that we use the average CPIW for the third quarter of 2017 as the base from which
we measure the increase (if any) in the average CPIW. The base average is
239.668, as shown in the table below.
Also shown in the table below, the average CPIW for the third quarter of 2018 is
246.352. Because this average exceeds 239.668 by 2.8 percent,
the COLA effective for December 2018 is 2.8 percent. The COLA calculation, with the result rounded to the nearest
onetenth of one percent, is:
(246.352  239.668)
/ 239.668 x 100 = 2.8 percent.

CPIW for— 
2017 
2018 
July 
238.617 
246.155 
August 
239.448 
246.336 
September 
240.939 
246.565 
Third quarter total 
719.004 
739.056 
Average (rounded to the nearest 0.001) 
239.668 
246.352 
