If you’re one of the some 67 million people receiving Social Security benefits, you probably pay close attention to the cost-of-living adjustment, or COLA, which is announced in October each year. The COLA is a change in your monthly benefit to ensure that your purchasing power remains the same even when prices rise due to inflation.

In 2023, the Social Security Administration announced that the COLA for 2024 benefits would increase by 3.2 percent, following an 8.7 percent rise the year before, the largest increase since 1981.

Here’s how the COLA is figured and who receives the benefit.

How the COLA is calculated

By law, the cost-of-living adjustment is based on the Consumer Price Index for Urban Wage Earners and Clerical Workers (CPI-W), a measure of inflation calculated by the Bureau of Labor Statistics (BLS).

To figure the index, the BLS administers a consumer expenditure survey to collect information every three months from approximately 7,000 individuals and families about the things they buy regularly — everything from personal care products to vehicle registration fees.

BLS data collectors then call retail stores, doctor’s offices and service establishments to determine the price changes for the approximately 80,000 items included in the CPI-W.

If there is no change in the CPI-W — which was the case in 2015 — there is no COLA for the following year. In 2016, there was a small increase of 0.3 percent in the COLA, which went into effect at the start of 2017.

Here’s a historical look at the COLA increases over the last 10 years:

Year COLA increase Year COLA increase
2023 3.2% 2018 2.8%
2022 8.7% 2017 2.0%
2021 5.9% 2016 0.3%
2020 1.3% 2015 0%
2019 1.6% 2014 1.7%

Source: Social Security Administration

The CPI-W and how it is calculated are sometimes the subject of debate. For instance, because it is based on a basket of products reflecting the spending of younger, working people, some critics say it doesn’t accurately measure the inflation experienced by older retirees, who may purchase more prescription drugs and medical services.

So a year with a low increase – or none at all – may really hurt Social Security recipients.

Why a COLA increase is so important

While COLA increases may seem paltry, even a small adjustment makes a big difference in the value of your dollar over time. For instance, while inflation has been extremely low from 2010 to 2020, it averaged around 2.4 percent a year from 1990 to 2020.

How big a difference can 2.4 percent inflation make? Let’s say you retire today at age 62 with a $2,000 monthly benefit. With inflation at 2.4 percent, you’d need a monthly benefit of $2,658 to maintain your purchasing power when you hit 74 years old. Another 10 years and you’d need $3,370 each month to have the same purchasing power as when you first retired. So at age 84 without a COLA, your money wouldn’t go nearly as far as it did when you first started receiving benefits.

Stashing money in a high-yielding certificate of deposit or a savings account is one way to help beat inflation. But it’s useful to have a diversified portfolio of investments that can grow over time and potentially earn more, helping you grow your purchasing power.

While inflation was relatively tame in the 2010s, it was much higher in 2021 and 2022. There have even been times—such as in the 1970s when legislation was enacted to provide COLAs—when inflation was in the double digits. For people living on a fixed income, the COLA is a critical safety net.

But assuming Social Security will cover all your bills in retirement is one of the biggest mistakes that near-retirees make. Here’s how much the average Social Security recipient gets.

Who receives a COLA?

While Social Security retirement recipients are the largest group to benefit from a COLA, they aren’t the only ones. Individuals receiving Supplemental Security Income, a federal program to help seniors age 65 or older, blind and disabled people, and individuals receiving disability payments, also get COLAs.

Military and federal civil service retirees have cost-of-living adjustments as well, and some unions negotiate COLAs in their contracts. Finally, eligibility for such government programs as food stamps and free school lunches is also tied to changes in the CPI-W.

Bottom line

A cost-of-living adjustment provides a key way that Social Security recipients and others can avoid having their purchasing power decline significantly over time. Those investing for retirement need to ensure that they have money there when they need it, which is why it’s so critical that workers not be too conservative in their other investments.