How much more Social Security do I get if I wait until 70?

Delayed retirement credits add two-thirds of 1% for each month you wait past full retirement age, which is 8% a year. The credits stop at 70, so there is no gain from waiting longer.

Example: a $2,000 benefit at 67 grows to about $2,480 at 70, which is $480 a month more. Compared with claiming at 62 ($1,400), the age-70 check is about 77% larger.

The cost is the checks you skip. Waiting from 67 to 70 gives up 36 checks of $2,000, or $72,000. At $480 a month more, it takes 150 months, until about age 79 and a half, to recover that before cost-of-living increases and taxes.

The extra credits also carry over to a surviving spouse. SSA computes a widow's or widower's benefit using the worker's full benefit plus the delayed retirement credits. They do not raise the spouse benefit paid while both are alive. If you delay, SSA says to still sign up for Medicare at 65, or coverage may be delayed and cost more.

The break-even age is a simple test, not the whole answer. It leaves out what you live on from 67 to 70, how much of your savings that uses, and how long the survivor in a couple might collect the larger check.