The etiquette in Rome is generally to hire a taxi at a taxi stand. Taxis do not cruise, but if free they may stop if you flag them down. They wait at stands but can also be called by phone, in which case you're charged a supplement (the meter will already been running when you’re picked up). The various taxi services are considered interchangeable and are referred to by their phone numbers rather than names. Taxicabs can be reserved the night before only if you're traveling to and from the airport or the train station. Only some taxis are equipped to take credit cards. Inquire when you phone to make the booking.
The meter starts at €3 during the day, €6.50 after 10 pm, and €4.50 on Sunday and holidays.
Supplemental charges, such as for luggage or even for pick up at Termini station, are added to the meter fare. When in doubt, always ask for a receipt (ricevuta). This will encourage the taxicab driver to be honest and charge you the correct amount. Between 10 pm and 6 am, women traveling alone via taxi are entitled to a 10% discount. Make sure to ask for it. Use only licensed, metered white or yellow cabs, identified by a numbered shield on the side, an illuminated taxi sign on the roof, and a plaque next to the license plate reading "servizio pubblico." Avoid unmarked, unauthorized, unmetered gypsy cabs (numerous at Rome airports and train stations), whose drivers actively solicit your trade and may demand astronomical fares.
Cab (06/6645, 06/3570, 06/8822, 06/5551, or 06/4157. www.3570.it.)