Carnival Splendor is a Splendor (Concordia)-class cruise ship, and is one of the latest of the Carnival Cruise ships to enter the fleet. She entered service on July 2, 2008. At 113,300 gross register tons (GRT), she was the largest ship in Carnival Cruise Lines until Carnival Dreamdebuted in September 2009. There are currently no plans to build another ship like her.

The ship was originally designed for Costa Cruises, and is similar in design to Costa Concordia, Costa Serena and their new sister ship, Costa Pacifica with a larger spa and children's facilities.
 The 3,006 passenger vessel offers a 21,000 sq ft (2,000 m2), state-of-the-art, indoor spa that consumes two forward decks, which is the largest spa ever on any Carnival ship. The spa features an elaborate thermal suite, a variety of health and beauty treatment rooms, and Carnival's first Thalasso therapy pool. Encircling the upper level of the spa is a winter garden with a ceremonial tea house. Spa access is complimentary for those staying in the non-smoking "spa" cabins on the Promenade and Spa decks. Those in other cabins may buy passes for the day or for the length of the voyage; typical fees are approximately $35 per day. Unlike with most Carnival ships, the sauna and steam rooms are part of this fee-based access and are not free to all passengers.
The 5,500 sq ft (510 m2) children's playroom located midship is also the largest in the Carnival fleet. Above the facility is a dedicated water play area, a first for Carnival Cruise Lines.Located at the stern of the ship is a new sports deck featuring arena-style seating for games and other events. A reservations only supper club is located atop the poolside Lido restaurant, providing diners with magnificent ocean vistas.The mid-ship pool, one of four on board, is enclosed by two full decks of glass walls. The area is covered with a two-deck-high retractable dome that can be closed during inclement weather. A large balcony encircles the upper deck of the pool area. There are flat screen televisions in every stateroom on the ship. Award winning shows are also offered on the ship.
Carnival Splendor's inaugural season began on July 2, 2008 with a cruise from Genoa, Italy to Dover, England, followed by a three-day cruise to Amsterdam. Thereafter followed five 12-day Northern Europe cruises from Dover to the Northern European ports of Copenhagen, Warnemunde, Helsinki,St. Petersburg, Tallinn, and Amsterdam. On 11 September 2008, the ship sailed to Southern Europe, to visit ports such as Civitavecchia (near Rome), Naples, Dubrovnik, Venice, Messina, Barcelona, Cannes, Livorno, Marmaris, Izmir, Istanbul, and Athens. She began her crossing of the Atlantic on the 3 November 2008, towards its new home port of Fort Lauderdale, in Florida.

In January 2009, Carnival Splendor embarked on a relocation from the Caribbean to the Pacific Ocean, its new home port being Long Beach, California. The ship is too wide for the Panama Canal, so it made the journey by sailing around Cape Horn. It was the first Carnival ship to have ever made this voyage. The relocation took 49 days, and included visits to ports in Dominica, Barbados, Brazil, Argentina, Uruguay, Chile, Peru,Ecuador, and Mexico.

In March 2009, Carnival Splendor was the host ship for Mayercraft Carrier 2, a four-day cruise from March 27 to March 31, from Los Angeles,California to Cabo San Lucas, Mexico hosted by musician John Mayer and featuring music and comedy shows.

 On November 8, 2010, at approximately 06:00 Pacific time, on the second day of a voyage from Long Beach to the Mexican Riviera, the ship experienced a fire in her engine room, cutting all electrical power. According to Carnival president, Gerry Cahill, a "crankcase split, and that's what caused the fire," adding it was isolated to the aft generator room. The fire was extinguished by the afternoon, and no one was injured. Nearly 4,500 passengers and crew members were onboard at the time.The crew was unable to restore power to the engines, and the ship was towed by tugboat to San Diego. Without power for air conditioning and refrigeration, passengers were fed rations delivered via U.S. Navy helicopters from the aircraft carrier USS Ronald Reagan.

Splendor was escorted by, and received aid and security assistance from the U.S. Coast Guard Cutter 
Morgenthau. Carnival Splendor arrived in San Diego under tow around sunrise on November 11, and docked around noon.

It was reported that Carnival has promised to give all passengers a full refund along with a voucher for a free cruise of equal value to their cruise on Splendor,along with reimbursement for their travel expenses.

The ship has three engines in the aft engine room and three in a forward engine room. Each generator is connected to the two switchboards. The failure of a single engine or generator should not normally cause a total power loss. Clark Dodge, former chief engineer for Washington State Ferries, said, "If things were designed properly, all the power shouldn't have gone out." The reasons for the total power loss are presently unclear and are under investigation.