WASHINGTON — The Supreme Court on Thursday reinforced the ability of corporations to write their own rules for resolving disputes with customers, finding that a group of merchants were bound by an arbitration agreement with American Express even if the terms made it prohibitively expensive to pursue some types of claims against the company.

Businesses generally regard arbitration as a cheaper and more efficient way to resolve disputes. Consumer advocates say the terms of the agreements can allow companies to escape accountability. The courts increasingly have sided with the companies, steadily limiting the circumstances in which customers can pursue claims outside of the arbitration process.

Thursday’s 5-to-3 ruling limits the ability of customers to pursue class actions. The conservative majority held that companies could require individual arbitration even if a class action is the only way to make the claim economically viable. The law, Justice Antonin Scalia wrote, does not “guarantee an affordable procedural path to the vindication of every claim.”

Business groups hailed the ruling as the end of a long legal battle.

“The Supreme Court today eliminated the last significant obstacle to adoption of fair, efficient arbitration systems that increase access to justice for consumers while reducing transaction costs for everyone,” Andrew J. Pincus, a lawyer at Mayer Brown who won a related Supreme Court arbitration case in 2011, said in a statement after the announcement.