The Social Security Administration has announced that monthly Social Security and Supplemental Security Income (SSI) benefits will increase 3.6 percent in 2012. The 3.6 percent cost-of-living adjustment (COLA) will begin with the January 2012 benefit payments. Increased payments for people on SSI will begin on December 30, 2011. For some beneficiaries, the increase in their Social Security benefit amount may be partially or completely offset by increases in Medicare premiums in 2012.