First generation cars were mostly marketed as the Optima, although the Kia Magentis name was used in Europe and Canada when sales began there in 2002.

The updated Optima was offered with a new 2.7 L engine, 4-speed automatic (the manual was dropped), and features such as full leather interior and alloy wheels were made standard.

In addition to the 2.4-liter inline-four and the 2.7-liter V6 offered in North America, globally the Optima/Magentis/Lotze was also available with smaller, 1.8- or 2.0-liter fours, as well as a 2.0-liter turbodiesel engine.

The second generation Optima was launched in Malaysia on 15 August 2007 powered by a 2.0-liter Theta DOHC CVVT engine with a 4-speed automatic transmission.

In addition to the revised exterior, length is also slightly increased by roughly 70 millimetres (2.8 in) to approximately 4,800 mm (190 in) long.

While the facelifted 2010 model was never officially launched, a very small number were imported for "evaluation" purposes, and eventually sold to the public as demos.

The completely redesigned Optima, sharing the same platform as its sibling Hyundai i40, named the Kia K5 in the South Korean and Chinese markets, made its world debut at the 2010 New York International Auto Show.

Lead designer of the TF in the team of Peter Schreyer and Miklos Kovacs was the Italian Davide Limongelli.

Standard equipment includes safety features such as electronic stability control (ESC) and ABS brakes, as well as Sirius Satellite Radio, cooled glove box, iPod connectivity, and handsfree Bluetooth phone operation.

Starting in October 2013, on LX models, Kia will offer the UVO infotainment system by Microsoft as part of the convenience package.

EX model options include Kia's new UVO infotainment system by Microsoft, integrated backup camera, and Proximity Key with Push-Button Start.

[14] The third generation Kia Optima is built and manufactured in West Point, Georgia, which began in 2011 with the 2012 model.

[18] The 2011 Kia Optima Hybrid was unveiled at the 2010 Los Angeles Auto Show, and was launched in the U.S. market in June 2011.

[23] The only externally apparent features that differentiate it from the Kia Optima are the hybrid badging, application specific wheel design, a lowered ride height by approximately 1 in (25 mm), and the availability of a special light platinum graphite paint color.

It also utilizes an active shutter system behind the upper grille, allowing the car to redirect airflow when the gas engine's heat levels allow (such as when the car is operating in EV mode to improve aerodynamics, or to assist in more rapid warming up of the gas engine).

In its 7,899-mile drive across the 48 states, the car recorded an average of 64.55 miles per gallon while consuming a total of five and a half tanks of gasoline.

For the Malaysian market, the fourth generation Kia Optima was launched in May 2017 powered by the Theta II 2.0 liter turbocharged four-cylinder gasoline engine with a 6-speed automatic transmission.

The Kia Optima PHEV shares the powertrain of the Hyundai Sonata PHEV, and like its sibling, it has a 9.8 kWh battery pack that delivers an all-electric range of 27 mi (43 km), but the Optima plug-in hybrid has a lower drag coefficient, which at 0.24 Cd is on par with the all-electric Tesla Model S. The Optima PHEV has an active grille, which automatically opens and closes at high and low speeds, contributing to reduce the Cd.

[31] The plug-in hybrid features a 50 kW electric motor and 2.0-liter “Nu” four-cylinder GDI engine, mated to a six-speed automatic transmission.

[48][49] The K5 facelift was revealed on 25 October 2023 in South Korea, and at the 2024 Chicago Auto Show for the 2025 model year in North America.

Changes include redesigned headlights and taillights, new front bumper with larger faux vents, new exhaust pipes for non-sportier trim levels, new exterior colours, new alloy wheel designs, an updated interior with a pair of 12 inches (30 cm) screens, the traditional gear lever replaced by a rotary selector, and new technological features.

[50][51] The facelifted K5 also has a new base engine, dropping the 1.6-liter turbo in favor of a naturally aspirated 2.5-liter 4 cylinder making 191 horsepower and 181 foot pounds of torque.

In June 2012, Michael Galati drove the Infinity Audio-sponsored Optima to Kia's first victory in round 8 of the 2012 season at Canadian Tire Motorsport Park in Bowmanville, Ontario, Canada, while teammate Mark Wilkins finished in second place.

[63] Kia Racing clinched the 2014 Pirelli World Challenge Grand Touring Sport (GTS) Class Manufacturer Championship in only its third season of competition.

Kia defeated rivals Ford, Chevrolet, Porsche, Aston Martin and Nissan to become the first Korean auto manufacturer to win the championship.

The race car weighs 2,950 pounds (1,338 kg) and is powered by an inline 4-cylinder engine generating 368 horsepower and uses a 6-speed sequential transmission.