Four classes on the same track at once, from twenty-four hours at Daytona to a hundred minutes on the streets of Long Beach — and a separate championship decided by the endurance races alone.
The IMSA SportsCar Championship — the WeatherTech SportsCar Championship under sponsorship — is North America's premier sports car series, raced in the United States and Canada. 2026 is the 56th season sanctioned by the International Motor Sports Association, whose lineage runs back to the 1971 IMSA GT Championship, and the thirteenth of this championship since the American Le Mans Series and the Rolex Sports Car Series merged for 2014. Eleven rounds run from the twenty-four-hour Rolex 24 at Daytona in January to Petit Le Mans in October, contested by four classes racing at the same time: GTP prototypes, LMP2, GTD Pro and GTD. Not every class enters every round, and the five endurance races also decide a championship of their own, the Michelin Endurance Cup.
For years North American sports car racing was split in two. Grand-Am Road Racing ran the Rolex Sports Car Series; the International Motor Sports Association, based in Braselton, Georgia, ran the American Le Mans Series. On 5 September 2012 the two announced they would merge, and that their premier series would combine for 2014.
The detail took a year. A preliminary class structure was agreed in January 2013: Grand-Am’s Daytona Prototype category and IMSA’s P2 would fold into a single prototype class, the American Le Mans Series’ Prototype Challenge cars would carry on, and the two GT classes would be rearranged into two. The only category that did not survive the merger was the American Le Mans Series’ P1.
The new series was revealed at Sebring on 14 March 2013, two days before the 12 Hours. The sanctioning body would stay IMSA, and the title — United SportsCar Racing — came from a public naming competition won by Louis Satterlee of Florida, a racer in the Florida Karting Championship Series. Tudor became title sponsor that September; WeatherTech replaced it from 2016.
Since then the top class has changed twice. Daytona Prototype International ran from 2019 to 2022, and GTP replaced it in 2023, built to IMSA’s LMDh rules and the Automobile Club de l’Ouest’s Le Mans Hypercar regulations — which is why the same marques now appear at the front of both the Rolex 24 and Le Mans.
Four classes sharing a circuit, a schedule where no two rounds are the same length, and two championships running at once.
GTP prototypes, LMP2, GTD Pro and GTD race together, with a prize in each class. Cars carry their class colour on the wing mirrors and windscreen so you can tell who is racing whom — because the traffic is a large part of the discipline.
Long Beach is GTP and GTD only. Detroit is GTP and GTD Pro. The Chevrolet Grand Prix at Canadian Tire Motorsport Park has no GTP at all, and the GT Challenge at VIR is GT cars only. Just six of the eleven rounds field all four classes, and five of those six are the endurance races.
The Michelin Endurance Cup is decided over the five endurance rounds on a 5–4–3–2 scale, and it awards points at intervals during each race rather than only at the finish: every six hours at Daytona, every four at Sebring, at half distance and the flag in the six-hour races, and at four, eight and ten hours at Petit Le Mans.
GTP and GTD Pro are open, with no restriction on line-ups. LMP2 teams may field only one gold-rated driver. GTD requires at least one silver or bronze amateur in every car and allows only one platinum driver — the same machinery as GTD Pro, a different kind of crew.
Two rounds run 1 hour 40 minutes, four run 2 hours 40, and five are endurance races of six hours or more — including the 12 Hours of Sebring, the 10-hour Petit Le Mans and the 24-hour Rolex 24 at Daytona.
Entries carry their biggest line-ups at the Rolex 24 — a GTP car may run four drivers — then fewer at Sebring and two for the sprint rounds. It is why Formula One, IndyCar and NASCAR names turn up in January and not in May.
Every round scores for the main championship. The five endurance rounds also score separately for the Michelin Endurance Cup, on a different scale and at fixed intervals inside the race.
GTP, LMP2 and GTD cars are all built to regulations compatible with the 24 Hours of Le Mans, so a team can take the same car to France.
| Pos | Race | Qualifying |
|---|---|---|
| 1st | 350 | 35 |
| 2nd | 320 | 32 |
| 3rd | 300 | 30 |
| 4th | 280 | 28 |
| 5th | 260 | 26 |
| 6th | 250 | 25 |
| 7th | 240 | 24 |
| 8th | 230 | 23 |
| 9th | 220 | 22 |
| 10th | 210 | 21 |
The Michelin Endurance Cup runs across the five endurance rounds on a 5–4–3–2 scale, and it hands out points at intervals inside each race rather than only at the flag — so a car can score at hour six of a twenty-four-hour race and again at the finish. It began in 2014 as the Tequila Patrón North American Endurance Cup; Michelin took the title in 2019.
Race points continue in tens below sixth place, down to 10 points for thirtieth and beyond, and qualifying pays exactly a tenth of the race scale. Every car entered counts as its own team, whether or not it is part of a two-car operation, and a manufacturer scores only for its highest-finishing car in each class.
| Rnd | Race | Length | Classes |
|---|---|---|---|
| 1 | Rolex 24 at Daytona | 24 hours | All |
| 2 | Mobil 1 Twelve Hours of Sebring | 12 hours | All |
| 3 | Acura Grand Prix of Long Beach | 1h 40m | GTP, GTD |
| 4 | Monterey SportsCar Championship | 2h 40m | GTP, GTD Pro, GTD |
| 5 | Detroit Sports Car Classic | 1h 40m | GTP, GTD Pro |
| 6 | Sahlen's Six Hours of The Glen | 6 hours | All |
| 7 | Chevrolet Grand Prix, Canadian Tire | 2h 40m | LMP2, GTD Pro, GTD |
| 8 | Motul SportsCar Endurance Grand Prix | 6 hours | All |
| 9 | Michelin GT Challenge at VIR | 2h 40m | GTD Pro, GTD |
| 10 | Battle on the Bricks, Indianapolis | 2h 40m | All |
| 11 | Motul Petit Le Mans | 10 hours | All |
Eleven rounds from 24–25 January at Daytona to 3 October at Road Atlanta. The five Michelin Endurance Cup rounds are the 24, 12, 6, 6 and 10-hour races. Road America's six-hour is the first endurance race of that length at the venue in IMSA history, and the Battle on the Bricks reverts to 2 hours 40 minutes after a longer run in 2024 and 2025.
The International Motor Sports Association runs the first IMSA GT Championship — the lineage this championship still counts its seasons from.
On 5 September, Grand-Am Road Racing announces a merger with IMSA, bringing the Rolex Sports Car Series and the American Le Mans Series together for 2014.
The class structure is agreed in January and the series revealed at Sebring in March. The sanctioning body stays IMSA, and the title United SportsCar Racing comes from a public contest won by Louis Satterlee, a Florida karting racer. Tudor signs as title sponsor in September.
WeatherTech replaces Tudor and the series becomes the WeatherTech SportsCar Championship. The GT Daytona class is introduced.
Michelin becomes the single tyre supplier for every class, replacing Continental, and NBC Sports takes exclusive United States coverage. LMP2 is split back out from the prototype class.
The professional GT class moves to FIA GT3 machinery, and USA Network replaces NBCSN as the series' cable home.
Daytona Prototype International gives way to GTP, built to IMSA's LMDh rules and the ACO's Le Mans Hypercar regulations — the same cars that race at Le Mans.
Eleven rounds, four classes. Jack Aitken leads GTP for Cadillac Whelen with two rounds to run.
Grand Touring Prototype, built to IMSA's LMDh rules and the ACO's Le Mans Hypercar regulations, so the same car can race at Le Mans. Porsche, Cadillac, Aston Martin, BMW and Acura all build one; chassis come from Multimatic, Dallara and Oreca. No restriction on driver line-ups.
Split back out from the prototype class for 2019, running the FIA and ACO's Global LMP2 regulations. Pro-am line-ups, with only one gold-rated driver permitted per car.
FIA GT3 cars in the hands of professional line-ups, replacing the old GTLM class. An open class with no driver rating restrictions.
Active since 2016 and running identical machinery to GTD Pro, but every car must field at least one silver or bronze amateur and may carry only one platinum driver.
Leads the 2026 GTP drivers' championship on 2,400 points in the No. 31 Cadillac Whelen, ahead of Laurin Heinrich on 2,282, with two rounds to run. His car also leads the GTP Teams' Championship and Cadillac leads the manufacturers, and he shares it across the season with Earl Bamber, Frederik Vesti and — at the Rolex 24 — Connor Zilisch.
GTLM champion in 2017, 2018 and 2020 and GTD Pro champion in 2025 — four titles across two classes, with three different co-drivers.
Champion in GTD in 2014, Prototype in 2016, DPi in 2019 and LMP2 in 2025 — four titles in four different classes.
Took the 2025 GTP drivers' championship for Porsche.
Leads GTP on 2,400 points in the No. 31 Cadillac Whelen with two rounds left.
GTD champion in 2016 and 2017, both alongside Alessandro Balzan.
Won the 2019 prototype title with Dane Cameron, adding it to a career in Formula One and IndyCar.
Prototype champion in 2017 with his brother Jordan, and still in GTP in 2026 with Cadillac Wayne Taylor Racing.
Won the Prototype Challenge title in 2017 with James French, before IndyCar.
North American sports car racing spent years divided between Grand-Am's Rolex Sports Car Series and the American Le Mans Series, each with its own prototypes, its own GT cars and its own audience. The 2012 merger put them on one grid for 2014. Only one category failed to survive it — the American Le Mans Series' P1.
The merged series did not get its title from a marketing agency. United SportsCar Racing was submitted through a public contest and won by Louis Satterlee, a Florida karting racer, and announced at Sebring in March 2013. Two sponsors have renamed it since.
GTP's LMDh and Le Mans Hypercar rules mean a manufacturer can build one prototype and race it on both sides of the Atlantic. It is why Porsche, Cadillac, Aston Martin, BMW and Acura are all in the class, and why the same marques now lead both the Rolex 24 and Le Mans. GTP, LMP2 and GTD cars are all built to regulations compatible with the French race.
With two rounds to run: the No. 31 Cadillac Whelen leads the GTP Teams' Championship and Cadillac the GTP manufacturers; the No. 04 CrowdStrike Racing by APR leads LMP2; the No. 1 Paul Miller Racing leads GTD Pro with BMW ahead of the marques; and the No. 27 Heart of Racing Team leads GTD with Aston Martin ahead of the marques. Manufacturers' championships are run for GTP, GTD Pro and GTD — not for single-specification LMP2.
North America's premier sports car series, run in the United States and Canada and known as the WeatherTech SportsCar Championship under sponsorship. 2026 is its thirteenth season and the 56th sanctioned by IMSA.
The International Motor Sports Association, the sanctioning body. It ran the first IMSA GT Championship in 1971, and the current championship counts its seasons from there.
Grand-Am Road Racing and IMSA announced a merger on 5 September 2012, combining the Rolex Sports Car Series and the American Le Mans Series into one championship for 2014.
GTP for prototypes built to LMDh and Le Mans Hypercar rules, LMP2 for Global LMP2 prototypes, GTD Pro for professional GT3 line-ups and GTD for GT3 cars with amateur drivers.
No. Long Beach is GTP and GTD only, Detroit is GTP and GTD Pro, Canadian Tire Motorsport Park has no GTP, and VIR is GT cars only. Six of the eleven 2026 rounds field all four classes.
A separate championship for drivers, teams and manufacturers decided over the five endurance rounds — Daytona, Sebring, Watkins Glen, Road America and Petit Le Mans. It scores 5–4–3–2 at intervals during each race rather than only at the finish.
350 for a race win, 320 for second, 300 for third and down in tens to 10 points for thirtieth and beyond. Qualifying pays exactly a tenth of that, 35 for pole. Each car counts as its own team, and a manufacturer scores only for its highest-finishing car in each class.
Anything from 1 hour 40 minutes at Long Beach and Detroit to twenty-four hours at Daytona. Four rounds run 2 hours 40 minutes and five are endurance races of six hours or more.
The cars are identical FIA GT3 machinery. GTD Pro is open, with no driver rating restrictions. GTD requires at least one silver or bronze amateur per car and allows only one platinum driver.
Yes. GTP, LMP2 and GTD cars are all built to regulations compatible with the 24 Hours of Le Mans, which is why the same marques appear at the front of both races.
In GTP, Jack Aitken on 2,400 points in the No. 31 Cadillac Whelen. Cadillac leads the GTP manufacturers, BMW leads GTD Pro and Aston Martin leads GTD.
Matt Campbell and Mathieu Jaminet in GTP, P.J. Hyett and Dane Cameron in LMP2, Antonio García and Alexander Sims in GTD Pro, and Philip Ellis and Russell Ward in GTD.
Antonio García and Dane Cameron have four each. García won GTLM in 2017, 2018 and 2020 and GTD Pro in 2025; Cameron took his in four different classes — GTD, Prototype, DPi and LMP2.
Daytona Prototype International was the top class from 2019 to 2022 and was replaced by GTP in 2023. GTLM was replaced by GTD Pro in 2022.
NBC Sports has held exclusive United States rights since 2019, with USA Network as the cable home since 2022.
Independent fan guide: IMSA revises its class structure and technical rules regularly, and the classes entered vary from round to round. Verify current sporting information with IMSA directly. Championship, team and driver names belong to their respective rights holders.
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