Health insurance is a legal contract between two or more parties that promises certain performance in exchange for considerations. A health insurance policy is considered a unilateral contract. This is because only one party (the insurer) is required to fulfill their obligation. While a policy owner may decide to terminate premium payments, as long as the payments are paid the insurer must meet their responsibility under the contract.

A health insurance policy can provide just one or any combination of certain benefits:

- Hospital, medical and surgical expenses resulting from sickness or an accident
- Accidental death or dismemberment
- Disability resulting from accident or sickness (sometimes this can also be referred to as