Insurance companies may be classified into two groups:
Life insurance companies, which sell life insurance, annuities and pensions products.
Non-life, general, or property/casualty insurance companies, which sell other types of insurance.
General insurance companies can be further divided into these sub categories.
Standard lines
Excess lines
In most countries, life and non-life insurers are subject to different regulatory regimes and different tax and accounting rules. The main reason for the distinction between the two types of company is that life, annuity, and pension business is very long-term in nature — coverage for life assurance or a pension can cover risks over many decades. By contrast, non-life insurance cover usually covers a shorter period, such as one year.
In the United States, standard line insurance companies are "mainstream" insurers. These are the companies that typically insure autos, homes or businesses. They use pattern or "cookie-cutter" policies without variation from one person to the next. They usually have lower premiums than excess lines and can sell directly to individuals. They are regulated by state laws that can restrict the amount they can charge for insurance policies.
Excess line insurance companies (also known as Excess and Surplus) typically insure risks not covered by the standard lines market. They are broadly referred as being all insurance placed with non-admitted insurers. Non-admitted insurers are not licensed in the states where the risks are located. These companies have more flexibility and can react faster than standard insurance companies because they are not required to file rates and forms as the "admitted" carriers do. However, they still have substantial regulatory requirements placed upon them. State laws generally require insurance placed with surplus line agents and brokers not to be available through standard licensed insurers.
Insurance companies are generally classified as either mutual or stock companies. Mutual companies are owned by the policyholders, while stockholders (who may or may not own policies) own stock insurance companies.
Demutualization of mutual insurers to form stock companies, as well as the formation of a hybrid known as a mutual holding company, became common in some countries, such as the United States, in the late 20th century.
Other possible forms for an insurance company include reciprocals, in which policyholders reciprocate in sharing risks, and Lloyd's organizations.
Insurance companies are rated by various agencies such as A. M. Best. The ratings include the company's financial strength, which measures its ability to pay claims. It also rates financial instruments issued by the insurance company, such as bonds, notes, and securitization products.
Reinsurance companies are insurance companies that sell policies to other insurance companies, allowing them to reduce their risks and protect themselves from very large losses. The reinsurance market is dominated by a few very large companies, with huge reserves. A reinsurer may also be a direct writer of insurance risks as well.
Captive insurance companies may be defined as limited-purpose insurance companies established with the specific objective of financing risks emanating from their parent group or groups. This definition can sometimes be extended to include some of the risks of the parent company's customers. In short, it is an in-house self-insurance vehicle. Captives may take the form of a "pure" entity (which is a 100% subsidiary of the self-insured parent company); of a "mutual" captive (which insures the collective risks of members of an industry); and of an "association" captive (which self-insures individual risks of the members of a professional, commercial or industrial association). Captives represent commercial, economic and tax advantages to their sponsors because of the reductions in costs they help create and for the ease of insurance risk management and the flexibility for cash flows they generate. Additionally, they may provide coverage of risks which is neither available nor offered in the traditional insurance market at reasonable prices.
The types of risk that a captive can underwrite for their parents include property damage, public and product liability, professional indemnity, employee benefits, employers' liability, motor and medical aid expenses. The captive's exposure to such risks may be limited by the use of reinsurance.
Captives are becoming an increasingly important component of the risk management and risk financing strategy of their parent. This can be understood against the following background:
heavy and increasing premium costs in almost every line of coverage;
difficulties in insuring certain types of fortuitous risk;
differential coverage standards in various parts of the world;
rating structures which reflect market trends rather than individual loss experience;
insufficient credit for deductibles and/or loss control efforts.
There are also companies known as 'insurance consultants'. Like a mortgage broker, these companies are paid a fee by the customer to shop around for the best insurance policy amongst many companies. Similar to an insurance consultant, an 'insurance broker' also shops around for the best insurance policy amongst many companies. However, with insurance brokers, the fee is usually paid in the form of commission from the insurer that is selected rather than directly from the client.
Neither insurance consultants nor insurance brokers are insurance companies and no risks are transferred to them in insurance transactions. Third party administrators are companies that perform underwriting and sometimes claims handling services for insurance companies. These companies often have special expertise that the insurance companies do not have.
The financial stability and strength of an insurance company should be a major consideration when buying an insurance contract. An insurance premium paid currently provides coverage for losses that might arise many years in the future. For that reason, the viability of the insurance carrier is very important. In recent years, a number of insurance companies have become insolvent, leaving their policyholders with no coverage (or coverage only from a government-backed insurance pool or other arrangement with less attractive payouts for losses). A number of independent rating agencies provide information and rate the financial viability of insurance companies.