iRacing has made the preliminary schedule for 2026 Season 4 available, revealing the circuits, race formats and weekly rotations planned across its Oval, Sports Car, Formula Car, Dirt Oval and Dirt Road championships. The new competitive season officially begins on September 15, 2026 at 00:00 UTC.
The schedule arrives shortly after the deployment of the major 2026 Season 4 build, which introduced the Aston Martin Valkyrie AMR-LMH, Caterham Academy, Caterham 420R and Gen 4 Grand National alongside completely rebuilt versions of Road America, Mid-Ohio Sports Car Course and The Milwaukee Mile.
Drivers can now begin planning their purchases and championship choices using the full iRacing 2026 Season 4 Preliminary Schedule PDF.
The document runs for more than 200 pages and provides individual schedules for the vast majority of iRacing’s official series, including tracks, race lengths, weather information, license requirements, race frequency, incident limits and other championship-specific details.
iRacing 2026 Season 4 starts September 15
The first regular week of Season 4 begins on September 15, following the current Week 13 transition period.
As usual, the season is built around 12 regular championship weeks, with most weekly series changing circuit every Tuesday.
The preliminary schedule covers everything from Rookie-level Mazda MX-5 and Formula Vee racing through GT3, prototypes, IMSA, NASCAR, Formula cars, dirt racing and endurance championships.
Because the document is currently described as preliminary, drivers should be aware that individual tracks, race lengths or other details may still be adjusted before or during the opening of the season.
The complete current version can be downloaded directly through the official iRacing 2026 Season 4 schedule.
New Caterham series join the Sports Car ladder
The arrival of the Caterham Academy and 420R also introduces dedicated championships for both new cars.
The Caterham Academy Challenge sits in the D Class Sports Car section of the schedule, while the faster Caterham 420R Cup appears at C Class.
The Academy series begins its season at Oulton Park Circuit – Fosters on September 15 and is scheduled to run every hour.
That creates a natural progression between the lower-powered Academy car and the considerably faster 420R, with both vehicles included together when purchasing the new Caterham package.
Both cars arrived with Season 4 and support rain racing and AI competition.
Gen 4 Grand National gets its own championship
The new Gen 4 Grand National also receives a dedicated official series.
The preliminary schedule lists the NASCAR Gen 4 Grand National Series – 2026 Season 4 Fixed, giving the new stock car a championship separate from the existing Gen 4 Cup.
The Grand National represents the second-tier stock car specification of the fourth-generation NASCAR era, using a shorter 105-inch wheelbase and approximately 600-650 horsepower.
Existing owners of the ARCA Menards / Gen 4 package received the Grand National as part of the Season 4 update at no additional cost.
Its inclusion in a dedicated schedule should give those drivers a clear reason to use the new car throughout the full 12-week season rather than treating it as occasional additional content.
MX-5 schedules confirmed for Rookie and Advanced series
The heavily updated Global Mazda MX-5 Cup remains central to iRacing’s Sports Car progression.
The Rookie Global Mazda MX-5 Cup opens Week 1 at Okayama International Circuit – Full Course, with races scheduled every 30 minutes. The Advanced Mazda MX-5 Cup by Heusinkveld begins at Daytona International Speedway – Road Course before moving to Okayama for Week 2.
That makes Season 4 particularly interesting for MX-5 drivers because the car itself has also received a substantial ground-up mechanical overhaul including updated suspension kinematics, tires, damping, driveline behaviour, aero data and handling.
Aston Martin Valkyrie joins prototype competition
The new Aston Martin Valkyrie AMR-LMH appears throughout the prototype side of the Season 4 schedule.
It joins the BMW M Hybrid V8, Cadillac V-Series.R, Acura ARX-06, Porsche 963 and Ferrari 499P in the Prototype Challenge, while also appearing in IMSA and endurance competition.
Prototype Challenge begins Week 1 at Indianapolis Motor Speedway – Road Course, followed by Road Atlanta, Fuji, Red Bull Ring and Long Beach during the opening portion of the season.
The preliminary calendar then takes the prototypes to venues including Circuit Gilles Villeneuve, Le Mans, Mexico City, Suzuka, Silverstone, Monza and Sebring.
IMSA begins Season 4 at Indianapolis
Both the Fixed and Open versions of the IMSA iRacing Series are scheduled to begin the new season at Indianapolis Motor Speedway – Road Course.
The championship includes GTP/LMH machinery, the Dallara P217 LMP2 and the current GT3 field.
For Season 4, that top prototype group now includes the Aston Martin Valkyrie AMR-LMH alongside the established GTP cars and Ferrari 499P. Week 2 moves to the refreshed Road Atlanta, followed by Fuji International Speedway during Week 3.
IMSA is also one of the series expected to benefit from iRacing’s new multiclass start system using separate pace cars for individual classes once that system completes its Week 13 testing.
GT3, Formula and Oval schedules are also included
The PDF is much broader than the headline Season 4 additions.
Sports Car drivers can inspect the complete schedules for championships including:
- GT3 Challenge Fixed by Fanatec
- GT Sprint Series by Simucube
- GT Endurance Series
- Ferrari 296 Challenge
- Porsche Cup
- GT4 Falken Tyre Challenge
- IMSA Michelin Pilot Challenge
- TCR Virtual Challenge
- Production Car Challenge
- Ring Meister
Formula Car schedules include the Formula 1600 Rookie Series, Formula Vee, FIA Formula 4 Challenge, regional F4 championships, Skip Barber, USF2000, Dallara F3 and higher-level open-wheel categories.
Oval competitors can meanwhile inspect the full NASCAR ladder, ARCA, Gen 4, Late Model, Modified, IndyCar and other championships, with Dirt Oval and Dirt Road series also receiving their complete Season 4 rotations.
Check the preliminary schedule before buying tracks
The release of the schedule is particularly useful for anyone planning to purchase circuits for a championship.
Rather than buying a track simply because it appears early in the season, drivers can now inspect all 12 weeks and determine how many events they realistically intend to enter.
It is also worth comparing multiple championships that use the same content. A circuit appearing in GT3, IMSA, MX-5, Formula and other series during the same season can provide considerably more value than one required for a single championship.
Because this remains a preliminary document, however, it is sensible to check the latest schedule before making purchases based entirely on a particular week.
The full document is available here: Download the iRacing 2026 Season 4 Preliminary Schedule PDF.
New drivers can access the service through an iRacing membership.
See you on the track!
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