What is the customer service number for fidelity? The customer support phone number of Fidelity Advisor is +1 877-208-0098 / 800-642-4585 (Click phone number to call).What is the toll free number for fidelity? Fidelity American Express Card toll free customer service number : +44 (0) 1273 868 900. Fidelity toll free customer service number : +1-(800)-343-3548.What is fidelity 800 number? The customer support phone number of Fidelity Investments Contact is +1(800)-343-354, 8800-544-6666, 800-544-6666 (Click phone number to call).What is fidelity investments phone number? Phone Number of Fidelity Investments is 800-544-6666 . Fidelity investments is a financial service industry that deals in finance and mutual product. It has 38,000 employees.