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You don’t have to begin collecting Social Security by age 70, but your benefit will not increase if you delay claiming past your 70th birthday. The delayed retirement credits that boost benefits for people who put off claiming Social Security past full retirement age stop accruing at 70, whether you've filed yet or not.
The Social Security Administration will be able to pay retroactive benefits covering up to six months prior to the month you filed the application. However, if you choose to collect retroactive benefits, you lose any delayed retirement credits you earned for those months.
Keep in mind
You don't have to be past 70 to collect retroactive benefits, but you do have to be past full retirement age, which is 66 and 6 months for people born in 1957 and two months later for those born in 1958. The age will gradually rise over the next few years to 67.
More on Social Security
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