Work credits are the measuring stick that the Social Security Administration uses to decide whether you've accrued enough earnings to qualify for benefits. It takes a minimum of 40 work credits to qualify for Social Security retirement benefits. In 2017, you need $1,300 in earnings to qualify for a single credit, and you can earn up to four credits per year.

The amount of earnings required for a quarter of coverage (QC) in 2019 is $1,360. "Quarter of coverage" is a legal term, but you may also see the term "Social Security credit" (or just "credit") used elsewhere. A QC is the basic unit for determining whether a worker is insured under the Social Security program. No matter how high your earnings may be, you can not earn more than 4 QC's in one year.

The amount of earnings required for a quarter of coverage (QC) in 2023 is $1,640.

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  As long as you have earned income such as wages, you're required to pay Social Security taxes on up to the annual payroll limitation — $147,000 in 2022. If you're past your full retirement age (FRA), there's no benefit reduction based on income.

• 3 Income Sources that Earn You Social Security Credits
• ssa.gov: Quarter of Coverage