"The bill I'm signing today is about a simple proposition: Americans who have worked hard all their life to earn an honest living should be able to retire with economic security and dignity — that's the entire purpose of the Social Security system," Biden said during a signing ceremony in the White House East Room. "This is a big deal," he said.

Advocates say the Social Security Fairness Act rights a decades-old disparity, though it will also put strain on Social Security Trust Funds, which face a looming insolvency crisis.