What causes an employee paid biweekly to receive three paychecks in a standard year?

Answer

The 26 pay periods not aligning perfectly with 12 calendar months

Since 26 does not divide evenly into 12 months, two months in a standard year will include an extra payday, resulting in three checks during those months.

What causes an employee paid biweekly to receive three paychecks in a standard year?
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