Certegy typically operates customer service during regular business hours, generally from Monday to Friday. The exact hours may vary, but many customer service departments are available from around 8 a.m. to 6 p.m. Eastern Standard Time. For the most accurate and up-to-date information regarding Certegy's customer service hours, it is advisable to check their official website. There, one can often find the specific hours of operation, as well as additional contact information if needed. Certegy places a strong emphasis on customer satisfaction, and their representatives are trained to assist with various inquiries related to payment processing and check services.