As electric vehicles (EVs) continue gaining momentum across the United States, California remains the country’s largest and most influential EV market. To support this rapid growth, the state has created a robust regulatory framework that ensures every piece of EV charging equipment meets strict standards for safety, accuracy, and transparency. One of the most important of these requirements is compliance with the California Type Evaluation Program (CTEP), a certification process that governs the accuracy of commercial EV charging stations—particularly those that bill customers for energy.
Administered by the Division of Measurement Standards (DMS) within the California Department of Food and Agriculture (CDFA), CTEP ensures that EV charging equipment operates similarly to traditional fuel pumps: precise, verifiable, and consumer-friendly. Any EV charger that measures electricity for commercial transactions is legally treated as a measuring device. As such, it must undergo rigorous testing before it can be sold, installed, or used in the state.
In this news feature, we take an in-depth look at what CTEP compliance means, why it matters, what requirements manufacturers must meet, and how the certification process works step by step. As California accelerates toward a fully electrified future, CTEP plays a pivotal role in building trust in EV charging infrastructure.
The California Type Evaluation Program is the official state certification program that verifies whether commercial measuring devices comply with California’s stringent regulatory standards. Traditionally applied to scales, fuel pumps, and meters, the program now extends to electric vehicle charging stations used for billing.
If an EV charger measures kilowatt-hours (kWh) or charging time and uses that measurement to determine the price a consumer pays, then it falls under CTEP jurisdiction. Before such a device can legally operate in California, the DMS must evaluate and approve it. If the device meets all technical, performance, and accuracy requirements, DMS issues a Certificate of Approval (COA).
Without this certificate, an EV charger cannot be used for commercial billing. This ensures every transaction is fair and accurate, protecting both consumers and charging providers.
EV adoption is growing, but consumers need confidence that they are paying a fair price for energy. Billing discrepancies—whether intentional or accidental—could undermine trust in EV infrastructure. CTEP significantly reduces this risk by ensuring standardization and accuracy in every charging session.
Just as fuel pumps must deliver the exact amount of gasoline displayed on the pump screen, EV chargers must deliver accurate electricity readings. CTEP testing ensures the measurement system meets strict tolerances and is not susceptible to malfunction or manipulation.
CTEP creates a level playing field. Every manufacturer must meet the same transparency and performance requirements, preventing untested or low-quality equipment from entering the market. This raises overall industry standards.
CTEP promotes consistency in what consumers see on charging screens—such as pricing, energy delivered, transaction details, and labeling. This makes the charging experience more predictable and user-friendly across different brands and networks.
California’s long-term EV strategy depends on a charging network that is not only widespread but also reliable. CTEP compliance helps reduce system failures, billing disputes, and customer complaints, contributing to a more dependable statewide charging ecosystem.
To receive CTEP certification, EV charger manufacturers must demonstrate that their products meet specific technical, operational, and documentation requirements.
Chargers must undergo witnessed testing in approved laboratories or test environments. These tests ensure the device’s energy measurement system is precise and consistently meets regulatory accuracy tolerances across different operating conditions.
NIST Handbook 44 is the national reference standard for all measuring devices in commercial use. EV chargers must comply with its requirements for:
measurement accuracy
device stability
operational consistency
system safeguards
Meeting NIST standards ensures that devices approved in California are aligned with national expectations for reliability.
Manufacturers must provide clear, accurate, and readable information on the charger’s display interface. This includes:
energy delivered (kWh)
session cost
price per unit
session time
equipment identification
California emphasizes transparency, so communication to the consumer must be unambiguous and standardized.
The manufacturer must submit detailed technical documentation, including:
device specifications
hardware components
software versions
calibration reports
laboratory test data
user information
This documentation helps DMS verify that the device meets all requirements before field evaluation begins.
Once a manufacturer applies, DMS assigns a CTEP evaluator to the case. The evaluator conducts a detailed review, inspecting the device both in a controlled environment and under actual operating conditions. Evaluators record their observations, including photographs, operational notes, and performance data, which are included in the COA documentation.
They assess multiple categories:
Evaluators perform precision tests, verify calibrations, assess charging output stability, and check measurement integrity across multiple charge cycles.
They verify that the measurement software is secure, tamper-resistant, and capable of maintaining accurate data logs.
All information displayed on the device must meet California’s legal requirements, including identification labels, usage descriptions, and certification markings.
The device must have built-in safeguards that prevent unauthorized adjustments or data tampering that could affect billing accuracy.
An EV charger will only pass if it meets or exceeds every requirement in the evaluation.
The path to obtaining CTEP approval includes several steps. Below is a clear overview of the process:
Manufacturers start by completing the Certificate of Approval application online through the California DMS portal. A $500 non-refundable fee must be submitted with the application.
After application review, the manufacturer is assigned a state evaluator. Both parties work together to ensure the device is ready for testing. This includes scheduling, documentation submissions, and arranging access to equipment and testing facilities.
In addition to the application fee, manufacturers must cover evaluator costs, including:
hourly service fees
travel expenses
equipment fees
per diem
These costs vary depending on the complexity of the charger and the duration of the evaluation.
The evaluator conducts the full inspection and performance testing. Observations, test results, photos, and device data are collected during this stage and included in the formal evaluation report.
If the EV charger passes all requirements, the evaluation is approved. If issues are found, the manufacturer may need to make corrections and schedule additional evaluation.
Once approved, the manufacturer receives the COA in the mail. This document proves that the device meets all legal requirements for commercial use in California.
The charger model is added to the statewide COA database. Only equipment with a valid listing can be sold, installed, or used for billing purposes in California.
Once listed, the charger is legally authorized to operate anywhere in the state where energy billing is required.
While CTEP is essential, it can pose several challenges for manufacturers:
Due to high demand and limited evaluators, the process can take months from application to approval.
Meeting NIST and California standards requires advanced hardware, precise metering systems, and secure software—elements that can be complex to implement.
Evaluator fees, lab costs, and engineering adjustments can be expensive, especially for smaller manufacturers.
Regulatory changes mean manufacturers must stay informed and continually update their equipment designs.
Despite these challenges, compliance remains mandatory for entering California’s lucrative EV market.
CTEP has influenced the industry far beyond California’s borders. Manufacturers now design products for nationwide use that inherently meet California’s stringent standards. This has accelerated innovation in:
metering accuracy
cybersecurity
data transparency
user interface quality
billing reliability
Furthermore, with federal initiatives such as NEVI (National Electric Vehicle Infrastructure), states increasingly look to California’s standards as a model. CTEP’s emphasis on accuracy and fraud prevention aligns closely with national priorities for charging reliability.
CTEP compliance is more than a regulatory requirement—it is a cornerstone of California’s strategy to create a trustworthy, transparent, and consumer-friendly EV charging ecosystem. By mandating accuracy, reliability, and clear communication, the California Type Evaluation Program ensures that EV chargers operate with the same accountability as traditional fuel pumps.
As EV adoption accelerates, the role of CTEP becomes even more important. It not only protects consumers but also elevates the industry, encouraging manufacturers to reach higher standards in design, testing, and performance. For any company looking to participate in California’s EV charging market, understanding and achieving CTEP certification is essential. It represents a commitment to quality, compliance, and the long-term success of electric transportation in the nation’s most influential EV state.
