What Is Member Month?

Member month refers to the number of individuals participating in an insurance plan each month. Member month is calculated by taking the number of individuals enrolled in a plan and multiplying that sum by the number of months in the policy. Member months help insurance companies calculate the average monthly premiums needed to be charged to their customers.

Key Takeaways

  • Member month refers to the number of individuals participating in an insurance plan each month.
  • Member month is calculated by multiplying the total number of individuals enrolled in a plan by the number of months in the policy.
  • One individual who has a policy that lasts one year creates twelve-member months (1 person x 12 months in the policy).
  • Member months help insurance companies calculate the average monthly premiums needed to be charged to their customers.

Understanding Member Month

Member month statistics are most commonly found in the reports of group insurance companies, such as group health plans. Determining how many individuals are enrolled in an insurance plan requires dividing the total number of member months by the number of months in the year.

Thus, if an insurer indicates that its member months total 1500, then the total number of individuals covered is around 125 (1,500 member months / 12 twelve months). The calculation is an approximation because some members may have policies that last one year, while others may have policies that last a shorter duration. For example, 1,500 member months could mean 125 members on annual policies, or it could mean 100 members on twelve-month policies and 50 members on six-month policies ([100 x 12 months] + [50 x 6 months] = 1,500 member months).

One individual who has a policy that lasts one year creates twelve-member months (1 person x 12 months in the policy). If that policy has a duration of six months, a single-member will generate six-member months (1 person x 6 months in the policy). For policies with multiple members, such as a family on a health insurance policy, the number of member months is larger because each family member counts. For example, a family of four enrolled in a twelve-month health insurance policy generates 48 member months (4 people x 12 months in the policy).

Member Months and PMPM

Member months can also be used to calculate the average monthly premiums. This is done by dividing the revenue generated by a group policy by the total member months, which gives an approximation for the average cost of a policy.

The member month statistic can also be used to determine PMPM, which stands for "cost per member per month." The PMPM calculation is often used by health insurance companies to determine the average cost of health care for each of their members. PMPM is also used outside the healthcare industry by companies that offer healthcare benefits to their employees. PMPM helps companies estimate how much each individual member should be charged for coverage.

How to Calculate PMPM

To calculate PMPM, choose the year for which to calculate PMPM, determine the number of people covered under the plan for that year, and determine the member months by multiplying the number of people covered (for all 12 months of the year) by 12. Then, determine the total cost of healthcare benefits for all of the members under the plan for this year. Divide the total cost of healthcare benefits for all members by the number of member months to arrive at the PMPM for the year.

Example of Member Months and PMPM

A business has 50 employees with an insurance plan through a local insurance company. All of the employee's policies are 12-month policies. As a result, the business has 600 member months with the insurance company (50 employees x 12 months).

The insurance company wants to calculate its cost per member per month (PMPM). The insurer determines that the total cost for providing the coverage to all of the company's employees equals $500,000 annually. The PMPM would equal $833 ($500,000 * 600 member months).

The insurance company would need to work with the business to determine what percentage would be paid by the business–on behalf of the employees–and which portion would be the employee's responsibility.