What causes boils on chin and now a lump under my chin both are very sore .?

Ingrown hairs: One common cause of boils in the chin area are ingrown hairs. This condition responds very well to laser hair removal.

Staph infection: This is a bacterial infection which requires oral antibiotics, based on culture and sensitivity. You may harboring bacteria in your nose and need to use bactroban (mupirocin) inside your nose one week per month to decrease recurrences.

Infection: Bacterial infection, usually staph, of hair follicle leading to suppurative inflammation. Predisposing factors like diabetes, ingrown hair, excessive moisture and immune deficiency favor multiple or recurrent boils. The "lump" may be a deep seated boil or infected lymph node. In either case it is time to see your doctor. Boils on the face are dangerous as infection can spread to the brain.