OPM Form 1515 at a glance
What it is: Military Service Deposit Election: the employee reads the information concerning rights to make a deposit for post-1956 military service and marks an "x" to indicate an election.
Where and when to file: Return the completed election form to the agency human resources office listed under Agency name and address. Election must be received by (mm/dd/yyyy).
A filled-in OPM Form 1515 example: the employee's and agency's boxes

How to fill out OPM Form 1515, box by box
Agency name and address

Check the appropriate box under Employee Election to indicate whether you will pay the deposit and return two copies of this form to the human resources office at the Agency name and address.
If you decide to make the deposit for military service, ask for instructions from the human resources office identified under Agency name and address.
Employee Election
Mark an "x" in the appropriate box under Employee Election to indicate your election.
Mark the box "I want to pay (or complete) this deposit" if you will make the necessary payment to your employing agency.
Mark the box "I do not want to pay (or complete) this deposit" only if you understand this decision is irrevocable.
Your decision about making this deposit may affect your rights under CSRS or the Federal Employees Retirement System (FERS).
More rules for OPM Form 1515
Instructions to the employing office: This form must be completed when an employee retires and agency records show that the employee has not made or completed a deposit for post-1956 military service. Give the employee three (3) copies of this form and these instructions for completing the form. Have the employee return two (2) signed and dated copies of the form. Attach one to the employee's records when you send them to the Office of Personnel Management (OPM). If the employee does not return a signed copy before you forward the records to OPM, please check the box Employee did not return election form. The employee should also be counseled regarding the minimum basic annuity if the payment of the deposit will not increase the annuity.
Sources
[1] OPM Form 1515, Military Service Deposit Election, U.S. Office of Personnel Management (the Official source link on this page).


