To get in touch with Fifth Third Bank, customers may refer to given customer service phone numbers to avail hassle free assistance. Fifth Third Bank Customer Service Phone Number:  1-866-671-5353 Commercial Support Center: 1-866-475-0729 International Customer Service Number: 1-513-579-5353 Toll-Free Fraud: 1-513-900-3080 Fifth Third Bank Personal Banking Customer Service Contact Details Customer Service Call Center: 1-800-972-3030 | Monday through Friday, 7 a.m. to 8 p.m. EST | Saturday, 8:30 a.m. to 5 p.m. EST | Closed Sunday. Lost or Stolen Bank Card: 1-800-782-0279 | 24 hrs, 7 days a week TDD: 1-800-546-7068 | Monday through Friday, 7 a.m. to 8 p.m. EST | Saturday, 8:30 a.m. to 5 p.m. EST | Closed Sunday. Apply for a Home Loan or Refinance: 1-866-351-5353 | Monday through Thursday, 8 a.m. to 8 p.m. EST | Friday, 8 a.m. to 6 p.m. EST | Saturday, 9 a.m. to 3 p.m. EST. Toll-Free International Fraud Support: 1-513-900-3080 Fifth Third Bank Business Banking Custo