A Reykjavík chauffeur service is private ground transport booked ahead at a price fixed before the trip starts, driven by a chauffeur holding a driver permit from Samgöngustofa, the Icelandic Transport Authority, and run by an operator licensed under Iceland's Act 120/2022 on taxi services. You do not flag it down and it is not sent by an app on demand. The car class, the pickup and the fare are settled before you land, whether the booking is a Keflavík airport transfer, an hourly car service around the capital, or a black car to a dinner at Harpa.
Price certainty is the point. A taxi from the KEF airport rank to Reykjavík usually runs on the meter and lands somewhere around ISK 20,000 to 25,000 depending on where you are staying. A reserved Reykjavík car service replaces the meter with one agreed figure, which Iceland's taxi law allows when the operator can prove the price was settled beforehand. RYDES quotes in euros; your card is charged in euros. Any VAT due and the airport's own kerb and pickup charges are already inside that number.
The same booking reaches well beyond the city. Blue Lagoon transfers on arrival day, Golden Circle private tours by the hour, south coast day trips to Seljalandsfoss and Vík, cruise port transfers from Skarfabakki, and a taxi alternative for evenings across Kópavogur, Garðabær and Hafnarfjörður. For weddings in town or out in the country, see wedding transportation, and for every point-to-point fare, the airport routes and day-trip routes listed below.