The City of Davenport's pay-by-phone number is 563-326-7707 option 1. Customers need to have their credit card information along with their invoice number and customer number to process their payment.  This information is available in the top right corner of your invoice. The service accepts American Express, Discover, MasterCard or Visa.  The City of Davenport does not add a convenience fee when you use a credit card.