Toronto has a large fleet of taxis; they are probably the most expensive way to traverse the city, but they come in handy when you are in a rush or have a lot of luggage in tow.

Fares 

As of July 2010, taxis have a meter drop fare of $4.25 to start your ride, with an additional $0.25 for every following 0.143 km (about two blocks) or for every 29 seconds waiting time. In addition, there is an extra charge for more than 4 passengers, $2.00 each additional person. HST (Harmonized Sales Tax) is included in the fare. A typical tip is 15-20% of the fare.  Most cabs accept credit cards or debit card payment via a Point of Sale machine (POS). There is an additional charge for the use of a card. Cash is still the fastest and cheapest way to pay. 

Fares are regulated by the city, so all taxis will have the same fares. For shorter distances, it may be more economical to share a cab among a few people than to pay separately for other forms of public transportation. Trips outside of the city are often unmetered, negotiate a fare with the driver beforehand. Standardized flat rate fares to the airport are available. Just ask the driver.

Hailing a Taxi

Taxis in the downtown area are relatively easy to catch just by standing on the curb of any major street and waving at an approaching cab with its rooftop light on. (The light is turned off when already engaged.) Also, major hotels often have a line of cabs waiting outside. In more residential or industrial areas you may need to call a cab in advance, and be prepared to wait up to fifteen minutes for its arrival.

Most taxis are midsized American and Japanese sedans that will seat four passengers.  The most common models in use are the Ford Taurus, Toyota Camry and Chevrolet Impala. Minivan taxis are rarer, so it is best to call in advance if you need one (there will be a $10 charge on top of the meter fare for requesting a minivan). Taxis are generally in good shape, and all are less than 5 years old. 

Taxis & Limos To or From Pearson International Airport

To get to the airport from anywhere in Toronto, you can hail any taxi on the street or get one from a hotel's taxi queue.  Drivers can offer a standardized airport flat rate based on the distance to the airport.

However, you can also book a licensed airport taxi or limousine to take you to or from Pearson International Airport at a pre-arranged rate Taxi & Limo Rates.  See the article Getting Downtown from Pearson Airport for links to airport taxi and limousine companies.

Pearson Airport is in the City of Mississauga. While any taxi can drop off passengers at the airport, it is illegal for Toronto taxis to pick up passengers at the airport without prior arrangement.  Some do anyway: if approaches by someone in the airport terminal offering you a ride, ignore them or report them to a uniformed airport employee. These are unlicensed and uninsured private vehicles.