You pay 100% of the premiums for your FEGLI Option B coverage. Unlike your Basic Life coverage which offers a level premium for all employees; Option B charges based on your age and the premiums increase every 5 years. Since Option B provides the most life insurance coverage under FEGLI it's the most expensive.
FEGLI charges the same rates regardless of whether or not you smoke, your overall health or if you are a male or female. If you don’t smoke and are reasonably healthy or if you are a female you may be overpaying for your Option B coverage.