Companies that need to file 5500’s are:
• Any company with a welfare plan covering 100 or more employees at the beginning of the plan year. A welfare plan consists of medical, dental, life insurance, educational assistance plans, group legal service plans, group vision plans, dependent care assistance plans and disability plans.
• Any company sponsoring a 401(k) needs to file regardless of the number of participants on the plan
If you fit either of these categories then you have to file a 5500. If you are using your SS#, I would suggest getting an EIN. http://www.irs.gov/Businesses/Small-Businesses-&-Self-Employed/Apply-for-an-Employer-Identification-Number-(EIN)-Online