Debt ratings upgrades can lower a company's borrowing costs. Moody's said the cruise company has benefited from strong cruise demand, debt reduction, and lower capital spending, which have helped to reduce the ratio of the company's debt to its earnings before interest, tax, depreciation, amortization, and rent.

Moody's upgraded Royal Caribbean's senior unsecured ratings to "Ba1," the highest junk rating, from "Ba2." The outlook is stable. The ratings action affects $4.3 billion of debt.

By: Reuters