A same day termination setting means that an employee's benefits will end the same day that they lose eligibility.
For example, an employee who is terminated on 6/2/2017 will have a final day of insurance coverage of 6/2/2017.
An end of the month benefits termination setting means that an employee will be covered until the last day of the month in which they are terminated.
For example, an employee who is terminated on 6/12/2017 will be covered until 6/30/2017 .
Termination settings aren't always selected by the company administrator. This is because they are based on the settings that the insurance carrier has on file. The insurance carrier allows the group to pick their waiting period, which is then used to determine the termination settings for that group. A group that selects a waiting period that has benefits becoming effective on the first of the month will often have a termination setting of final day of the month. A group that selects a waiting period that has benefits becoming effective mid month will often have a termination setting of same day. This is because termination settings are built to match the waiting period and billing cycles.