Top 10 Insurance Companies By The Metrics

There are a number of ways to rank the size of insurance companies. Companies can be measured by their market capitalization (the value of the company on a stock exchange) or by using sales figures such as net premiums written in a year or how many policies were sold. (For more, see: Which insurance policies do I really need?)

Largest Public Insurance Companies by Market Capitalization

Investors can buy shares of publicly traded companies in the insurance industry. The largest insurance companies as of Q1 2014 by market capitalization on the world stock exchanges are:

Non-health Insurance Companies:

Company Name Market Capitalization
Berkshire Hathaway (BRK.A) $308 billion
China Life Insurance (LFC) $80 billion
Allianz (AZSEY) $76.8 billion
American International Group (AIG) $72.3 billion
Ping An of China (PNGAY) $65.6 billion
MetLife (MET) $59.4 billion
AXA (AXA) $57.8 billion
AIA Group Hong Kong (AAIGF) $54.4 billion
ING Groep (ING) $54.4 billion
Zurich Insurance (ZURVY) $45.4 Billion

(Source: Thompson Reuters)

Health Insurance and Managed Health Care Companies:

Company Name Market Capitalization
United Healthcare (UNH) $91.8 billion
Wellpoint (WLP) $34.3 billion
Aetna (AET) $29.8 billion
CIGNA Corp. (CI) $26.8 billion
Humana (HUM) $21.1 billion
Centene Corp. (CNC) $5.7 billion
Health Net, Inc. (HNT) $3.9 billion
WellCare Health Plans (WCG) $3.1 billion
Healthspring (HS) $3.7 billion
Molina Healthcare (MOH) $2.4 billion

(Source: Thompson Reuters)

Not all insurance companies are publicly traded. In fact, many insurers are structured as mutual companies where policy holders of participating policies are essentially partial owners of the company. The mutual company model for an insurance company dates back hundred of years, and there are certain benefits conferred on policyholders that do not exist with publicly traded (stock company) insurers. (For more, see: The Industry Handbook: The Insurance Industry.)

Largest Insurance Companies by Sales and Product Line

It is useful to differentiate between the type of insurance, or line, that is being considered when considering the largest insurance companies. Using sales data is helpful as some of the largest insurance companies in the United States are not publicly traded and therefore their market value is not easily ascertained.

Property & Casualty

Property casualty insurers write policies covering property such as real estate, dwellings, cars and other vehicles. They also write policies dealing with liabilities that may be incurred by accident or negligence related to those properties to defray the cost of lawsuits or medical damages resulting from such incidents.

The top U.S. property casualty companies in 2013 by net premiums written (the amount of money that non-life policies can expect to receive over the life of the contract, less commissions and costs) are:

Company Net Premiums Written
State Farm Group $50.8 billion
Allstate Insurance Group (ALL) $24.8 billion
Liberty Mutual $21.5 billion
Berkshire Hathaway (includes GEICO) $21.4 billion
Travelers Group (TRV) $20.6 billion
American International Group (AIG) $19.7 billion
Nationwide Group $14.5 billion
Progressive Insurance Group (PGR) $14.5 billion
Farmers Insurance Group $14.1 billion
USAA Group $10.7 billion

(Source A.M. Best)

Life Insurance Companies

Life Insurance companies promise to pay out a lump sum benefit upon the death of the insured. Although actuarial science has created mortality tables to accurately estimate the future liability of policies to be paid, having financial strength ensures that these companies can meet all of their obligations while still earning a profit.

Life Insurance companies in the U.S. can be ranked by direct premium written (the amount of new policies written directly and not re-insured). For 2013:

Company Total Direct Premium Market Share
MetLife (MET) $11.5 billion 7.98%
Northwestern Mutual $9.4 billion 6.55%
Prudential of America (PRU) $8.4 billion 5.79%
New York Life $7.8 billion 5.42%
Lincoln National $6.1 billion 4.27%
MassMutual $5.1 billion 3.52%
John Hancock $4.8 billion 3.37%
Aegon (AEG) $4.1 billion 2.82%
State Farm $4.0 billion 2.79%
Guardian Life Insurance Co. $3.4 billion 2.34%

(Source: NAIC)

Health Insurance Companies

Health insurance companies provide policies to cover all or part of policyholder's health and medical costs. Policies may be purchased individually or through an employer. Technically, the United States government is the largest health insurance provider in America through the Medicare program, Social Security and with Medicaid administered by individual states. (For more, see: 5 Things You Need To Know About Obamacare.)

The largest non-government sponsored U.S. health insurance companies measured by total direct premium collected in 2007 was:

Company Total Direct Premium Market Share
United Healthcare (UNH) $66.8 billion 11.70%
Wellpoint Group (WLP) $55.7 billion 9.75%
Kaiser Permanente $43.7 billion 7.66%
Humana (HUM) $21.7 billion 3.81%
Aetna (AET) $21.7 billion 3.81%
Health Care Service Corp $14.9 billion 2.60%
American Family $11.6 billion 2.04%
Highmark $11.4 billion 2.01%
Blue Cross/Blue Shield $9.8 billion 1.72%
Cigna (CI) $9.6 billion 1.69%

(Source: NAIC. Caveat emptor: The sales data on health insurance companies is from 2007, the last year of available data. The Affordable Care Act (aka 'Obamacare') may have altered these standings.)

The Bottom Line

Ranking the largest insurance companies can be done in a number of ways. Shares of publicly traded companies can be bought to help build a well-diversified investment portfolio that has exposure to the financial and healthcare sectors. Identifying which types of insurance a company primarily deals with helps determine which firms are competitors and which really are not. Looking at sales figures, or premiums collected in a year, one can also see how public companies stack up against privately held or mutual companies which make up a large segment of the industry.