Enter the end date and start date of service into the calculator to determine the length of service.

Length of Service Formula

The following formula is used to calculate the length of service.

LOS = E - S


  • LOS is the length of service (in years, months, days, etc.) E is the end date of service (date) S is the start date of service (date)

To calculate the length of service, subtract the start date of service from the end date of service. The result will be the length of service. This can be calculated in years, months, days, etc. depending on the level of precision required.

What is a Length of Service?

Length of Service (LOS) refers to the total duration of time that an employee has been employed by a specific company or organization. It is often used to determine eligibility for certain benefits, calculate pension or retirement plans, and sometimes to determine the amount of vacation or sick leave an employee can accrive. It can also be a factor in decisions about promotions or layoffs, with longer-serving employees often having more job security.

How to Calculate Length of Service?

The following steps outline how to calculate the Length Of Service (LOS).

  1. First, determine the end date of service (E).
  2. Next, determine the start date of service (S).
  3. Next, gather the formula from above = LOS = E – S.
  4. Finally, calculate the Length Of Service.
  5. After inserting the variables and calculating the result, check your answer with the calculator above.

Example Problem : 

Use the following variables as an example problem to test your knowledge.

End date of service (E) = June 30, 2022

Start date of service (S) = January 1, 2018