North American Charging Standard
The North American Charging Standard, also known as the North American Charging System and officially designated SAE J3400, is an electric vehicle charging connector developed by Tesla, Inc. and maintained by SAE International. It has been endorsed by the U.S. government since December 2023.
Tesla introduced the physical connector design, originally called the Tesla charging connector, with the Model S in 2012; however, it was not until 2021 that Tesla vehicles began supporting the expanded communications protocol that is specified as part of NACS. In 2022, Tesla opened the standard to other manufacturers, and SAE International formally standardized it in 2023. NACS uses a single compact connector for both AC and DC charging, sharing common pins for both modes, unlike other systems that require different or larger connectors for DC fast charging.
Between May 2023 and February 2024, most major automakers announced plans to adopt NACS for their North American EVs beginning with the 2025 model year, replacing the Combined Charging System Combo 1 connector. Access to the Tesla Supercharger network, regarded as more reliable and extensive than other networks, was cited as a major factor in the transition. Several EV charging network operators and charging equipment manufacturers also announced plans to adopt NACS connectors.
Background
After initial testing allowing non-Tesla EVs to use Tesla Supercharger stations in Europe in December 2019, Tesla began to test a proprietary dual-connector "Magic Dock" connector at select North American Supercharger locations in March 2023. Magic Dock allows for an EV to charge with either a NACS or CCS1 connector, which would provide the technical capability for almost all battery electric vehicles the chance to charge. While most of Tesla's North American Supercharger locations currently provide exclusively NACS connectors, 92 locations with V3 posts and 44 with V4 supported the Magic Dock adapter as of February 2025.History
Tesla developed a proprietary charging connector for the Model S in 2012 and used it on all subsequent vehicles, including the Model X, Model 3, Model Y, and Cybertruck. As part of its business strategy, the company also built the Tesla Supercharger network across the United States.Following the passage of the Infrastructure Investment and Jobs Act in 2021, the U.S. government announced $7.5billion in subsidies to support the development of a nationwide network of fast chargers at least every along America's highways. To qualify for funding, chargers were required to be accessible to multiple brands of electric vehicles.
In response, in November 2022, Tesla introduced the North American Charging Standard, an open standard based on the physical design of its earlier proprietary connector. However, unlike the original Tesla connector, which used CAN bus communication, NACS employs the ISO 15118 protocol used by CCS1, allowing for vehicles with a CCS1 port to charge at a NACS station using an adapter, and allowing Tesla vehicles to charge at a CCS1 station using an adapter. Tesla vehicles built before 2021 require an ECU retrofit to support charging at a CCS1 station. The Supercharger network remains backward compatible with both the original connector and NACS.
Tesla promoted NACS as offering several advantages, including a more compact design, a Tesla vehicle fleet that outnumbered CCS1-equipped vehicles by a margin of two to one, and a Supercharger network with 60 percent more stalls than all CCS1-equipped networks combined. Commentators described the move as a last-ditch effort to save the Tesla connector as federal funding under the Infrastructure Investment and Jobs Act supported the expansion of CCS1 infrastructure.
In May 2023, Ford Motor Company became the first major automaker to announce plans to adopt NACS. Ford stated that beginning in 2025, all new electric vehicles would feature native NACS ports, with earlier models able to use NACS chargers through an adapter starting in 2024. Ford's announcement began a rapid shift in the industry, with other manufacturers making similar announcements throughout 2023 and early 2024, leading to widespread industry adoption.
Observers noted that the broad shift reflected recognition of the Tesla Supercharger network as among the most reliable and extensive, and that NACS offered advantages in design and usability. Analysts also suggested that charging infrastructure could become a recurring revenue source for Tesla.
On June 27, 2023, SAE International announced plans to standardize the NACS connector as SAE J3400. In August 2023, Tesla licensed the design to Volex to manufacture NACS components. SAE published the "technical information report" on December 18, 2023, and the "recommended practice", with "NACS" redefined as the "North American Charging System," on September 30, 2024.
Following widespread industry adoption, the U.S. government publicly endorsed NACS in December 2023. The Federal Highway Administration announced plans to integrate the SAE-standard NACS plug into eligibility criteria for federal charging infrastructure funding.
Tesla officially opened more than 15,000 Supercharger stalls to Ford owners on February 29, 2024. The company reported that technicians had retrofitted many stalls with updated electronics to support both CAN bus and ISO 15118 protocols, enabling compatibility with CCS1-equipped vehicles. Tesla indicated that retrofitting work would continue across its network.
Description
The NACS connector supports both alternating current charging and direct current fast charging.Technical specifications
The NACS connector is available in two DC configurations: one supporting up to 500volts and another supporting up to 1000V. The higher voltage version is backward compatible with the former.No maximum current rating is specified for NACS. Any amount of current is permissible, provided that the temperature of the connector’s interface does not exceed. Tesla has reported operating the connector at continuous currents up to 900amperes.
For DC fast charging, the current version 4 Tesla Supercharger delivers up to 325kilowatts of power, though this is not the maximum capacity of the NACS connector.
For AC charging, the NACS system can supply up to 80amps at 277V, derived from a three-phase commercial power supply at 480V, yielding 22.16kW. However, in typical configurations, NACS provides up to 48amps of current at 240V, yielding 11.5kW.
Operation
The NACS connector features a single button located on the top center of the handle. Pressing the button emits a UHF signal. When the connector is securely locked in place, the signal triggers the vehicle to retract the latch that holds the connector in place. If the connector is not locked in place, the signal prompts the vehicle to open the door covering the inlet.Pin layout
The NACS connector has a five-pin layout. Two primary pins are used for both AC charging and DC fast charging:- DC+/L1: Provides the positive side of the DC voltage link or, in AC mode, serves as Line 1 in a split-phase connection or as the sole line in a single-phase connection.
- DC−/L2: Provides the negative side of the DC voltage link or, in AC mode, serves as Line 2 in a split-phase connection or as the neutral in a single-phase connection.
- G : Connects the earth to the vehicle’s chassis. This pin also serves as a reference for the CP and PP signals and is used to measure electrical isolation.
- CP : A digital communication path used to exchange information about charging state and current, in accordance with IEC 61851. Power-line communication is superimposed on the control pilot during DC charging.
- PP : Carries a low-voltage signal to determine the connector’s status. When the release button on the plug is pressed, a switch on the proximity pilot circuit opens, interrupting the flow of electricity.
Adoption
Automakers
In May 2023, the Ford Motor Company became the first major automaker to announce that it would use NACS with its electric vehicles. Over the next two years, nearly every automaker selling vehicles in the North American market pledged to switch to NACS.Initially, owners of cars with CCS1 will be offered a NACS adapter to enable charging at Tesla's network, then, starting in 2025, the manufacturers will begin building NACS ports into new cars. In February, Ford became the first automaker to offer an adapter to customers, allowing Ford vehicles to charge with the adapter on a majority of Tesla's V3 and V4 chargers.
The automakers that committed to this transition are:
| Company | Announced | Supercharger access | |
| Ford | May 25, 2023 | February 29, 2024 | |
| General Motors | June 8, 2023 | September 18, 2024 | |
| Rivian | June 21, 2023 | March 18, 2024 | |
| Volvo | June 27, 2023 | October 29, 2024 | |
| Polestar | June 29, 2023 | October 29, 2024 | |
| Mercedes-Benz | July 7, 2023 | February 4, 2025 | |
| Nissan | July 19, 2023 | December 10, 2024 | |
| Honda | August 18, 2023 | July 22, 2025 | |
| Jaguar Land Rover | September 21, 2023 | August 8, 2025 | |
| Hyundai/Genesis | October 5, 2023 | March 25, 2025 | |
| Kia | October 5, 2023 | April 24, 2025 | |
| BMW Group | October 17, 2023 | December 10, 2025 | |
| Toyota | October 19, 2023 | October 22, 2025 | |
| Subaru | November 1, 2023 | October 22, 2025 | |
| Lucid | November 6, 2023 | January 31, 2025 | |
| Volkswagen Group | December 19, 2023 | November 18, 2025 | |
| Mazda | January 16, 2024 | ||
| Stellantis | February 2, 2024 |
Mitsubishi Motors is the only major automaker that has not announced plans to adopt NACS.