NEW YORK, Aug 15 (Reuters) - Aetna Inc on Monday said that due to financial losses on Obamacare plans, it only will sell individual insurance on exchanges in four states next year.

The No. 3 U.S. health insurer said it would continue to sell plans on the exchanges created under President Barack Obama's national healthcare reform law in Delaware, Iowa, Nebraska and Virginia in 2017.

It currently sells these plans, which are eligible for income-based government subsidies, in 15 states. Aetna already disclosed in early August that it would not expand its individual insurance business into new states as planned. It said it would closely review its participation in all of the 15 states where it sells plans in 2016.

(Reporting by Caroline Humer; editing by Diane Craft)