Skylight Financial has closes on a $12.8 million-round of funding, led by Chicago-based GTCR Golder Rauner and Walnut Investment Partners, an existing investor in Skylight.

Based in Atlanta, Skylight says it will use the funding to help accelerate the company’s geographic expansion. Skylight has customers in 46 states, and over 60 percent of Fortune 100 companies currently have employees with a Skylight account.

Founded in 1998, the company has raised about $25 million to date. Skylight recently signed a deal in partnership with U.S. Bancorp to provide its payroll services to Ryder System Inc.

GTCR says it partnered with O.G. Greene, chief executive officer of Skylight, and senior management of the company in the investment.

Prior to joining Skylight, Greene served as the CEO of National Data Corporation, a provider of payment services to the credit card and health care industries. He also served as the chief operating officer of First Financial Management Company and as the CEO of both Speer Communications and Gridnet.

“I am thrilled to have partnered with GTCR to execute the company’s growth strategy,” Green said in a statement. “GTCR is a great long-term partner for our customers and employees given their expertise in payments processing. This investment is a vote of confidence in Skylight’s on-line debit operating model.”

Skylight provides FDIC-insured “checkless” bank accounts to employers and underserved members of the population. These accounts allow individuals to use a Skylight-issued card for ATM transactions and debit purchases at the point of sale.

“Skylight is an exciting investment opportunity for GTCR,” Collin Roche, principal at GTCR, said in a statement. “We believe that the company will continue its rapid growth as it expands its geographic reach and creates new partnerships with employers. We look forward to working with O.G. Greene and the other managers at Skylight to continue to build the company’s momentum.”

Skylight Financial:

GTCR Golder Rauner: