I am an employer of less than 50 employees, but my company is “self-insured”, so we must report to the IRS. Which forms do I use? 1094 and 1095 B or C?

Normally employers file the 1094/5 C however there is a condition when the employer would file the 1094/5 B.
The employer is responsible for filing IRS Form 1095-B only if two conditions apply: It offers health coverage to its employees, and it is completely “self-insured.” This means the company itself pays its employees’ medical bills, rather than an insurance company. A company that doesn’t meet both conditions won’t have to deal with Form 1095-B. Its employees might still receive a 1095-B, but it would come from their insurance company, not the employer.