In 1853, the Annuity department separated from Aetna Insurance to form the Aetna Life Insurance Company. In 1861, Aetna began selling life insurance policies which paid dividends to policyholders just like mutual life insurance policies.
By 1864, Aetna had increased its volume of business by 600% over 1861 and its annual premium income ninefold, exceeding one million dollars which allowed it to meet the stringent regulatory requirements placed on life insurance companies in Massachusetts and New York and in 1865, Aetna started doing business in these states.
In 1907, Aetna moved into other insurance areas creating a casualty subsidiary to handle items such as automobile property coverage as well as related lines such as collision and damage which rolled into the Aetna Casualty and Surety Company.
In 2017, CVS Health announced the acquisition of Aetna for $69 billion.