Is the Social Security delayed benefit increase in addition to COLA?

I understand that delaying taking social security from full retirement age (67, based on my birth year) until age 70 results in a 24% increase in the monthly benefit, or 8% per year.

If so, is it additional or multiplicative? By that I mean if the COLA for year 1 is 5%, does that mean my benefit in nominal terms goes up by 5% then by 8% for a total of 13.4% or does it go up by the combined amount of 5% + 8% = 13%?

• The Social Security calculators are assuming that your current rate of earnings will continue till age 70. Since benefits are computed from the SS earnings of your highest 35 years, for many people, this means that low-salaried years at the beginning of the career are being replaced by high-earnings years at the end. But if your salary goes down, e.g. you switch to part-time work, then the estimate can be off by quite a bit. You don't get COLAs until you start drawing Social Security benefits. Apr 2, 2014 at 23:23
• I thought that the 8% was if one retired at 62, but delayed the start of benefits. And the 8% was real, i.e. in addition to inflation. Dilip's answer and mine would be exactly opposite, so we need to get researching to help answer this. Apr 3, 2014 at 0:38
• @DilipSarwate You're right that there are no COLAs until retirement (strictly speaking) but the PIA bend points used to determine the initial year's benefit are also indexed. See ssa.gov/OACT/cola/piaformula.html and ssa.gov/OACT/cola/bendpoints.html ... The bend points are indexed according to the National Average Wage Index, not the CPI. Apr 3, 2014 at 2:15
• I suggest a look at socialsecurity.gov/OACT/quickcalc/index.html When I enter that I've already stopped working, and ask for my benefit in 2024 (age 62) or 2029 (age 67) I see an increase of 63%, despite the same site's infographic showing a 44% increase between those same ages. Apr 3, 2014 at 2:23
• Try the more detailed downloadable calculator at this URL Apr 3, 2014 at 2:44