The average price of a taxi from the Port of Civitavecchia to Rome is around €140, however, surcharges for tolls and rides at night may apply, as well as for extra luggage. Unfortunately, local taxis aren't allowed in the port.
People Also Ask
All Rome city taxis are required by law to have POS machines. This means you SHOULD be able to pay with a credit card. I say should because sometimes you will find these POS machines to mysteriously be out of order. On the other hand, since Covid, many drivers are happy to use a contact-less pay system.