Gateway One Lending & Finance, which services car loans for consumers, is closing its Anaheim office and laying off all 137 of its workers, according to a notice filed with the state.

The company informed the state Employment Development Department in a letter received Feb. 3 that the last day for the workers will be April 3. The layoffs will affect the entire workforce at the Riverview Drive office.

Gateway One services subprime car loans, with most of its business coming from borrowers referred by dealerships. It is owned by Detroit-based TCF Financial Corp., a banking company that has more than 300 locations, mostly in the Midwest. TCF purchased Gateway One in 2011.

At one point, Gateway One had relationships with more than 3,200 car dealers in 30 states.

In December, Gateway One announced it was selling loan assets worth $1.1 billion to Santander Consumer USA Holdings, a subsidiary of a global financial company that has its roots in an iconic Spanish bank.

The deal includes the conversion of an additional $500 million in assets that Santander will sub-service for Gateway One. Santander’s North American operations are based in Boston.

The two deals mean that the entire staff in Anaheim, which includes accountants, collection agents, bankruptcy specialists and executive staff, is no longer needed.

Tom Wennerberg, a spokesman for TCF Financial, said that he did not know if any of the employees would be offered jobs within the organization but that this decision would be up to Santander. He declined to talk about any severance offers or other forms of compensation, saying that this information was confidential.

He added that the Anaheim office was TCF’s only operation in California. Santander did not reply to requests for comment.

Gateway One informed the state of the development in compliance with the Worker Adjustment and Retaining Notification Act, which requires at least 60 days of advance notice in the event of a major layoff.