Colorado Clean Trucks


Please note: If you would like to request a Spanish interpretation, please email cdphe_apcd_outreach@state.co.us.

Tenga en cuenta: Si desea solicitar interpretación al español, envíe un mensaje por correo electrónico a cdphe_apcd_outreach@state.co.us.



The Colorado Air Quality Control Commission adopted three clean trucking rules in April 2023. These include:

The three rules involved changes to Colorado Air Quality Control Commission Regulation Regulation 20, 5 CCR 1001-24. Although the regulation also covers light-duty passenger vehicles, the clean trucking rules only cover vehicles with a gross weight rating of 8,501 pounds and greater. The three clean trucking rules will:

  • Reduce greenhouse gas emissions that cause climate change and make progress towards goals in the Colorado Greenhouse Gas Pollution Reduction Roadmap.
  • Reduce air pollution emissions that form harmful ground-level ozone.
  • Protect air quality for communities near busy roads and highways.

The Advanced Clean Trucks Rule

The Advance Clean Trucks Rule requires manufacturers of medium- and heavy-duty on-road vehicles to sell an increasing percentage of zero-emission vehicles from model year 2027 and beyond. Zero-emission vehicle types include electric, hydrogen, and plug-in hybrids. The sales standard applies to trucks offered for sale or lease in Colorado.

Colorado’s Advanced Clean Trucks Rule does not ban the sale of vehicles that run on gas or diesel. Rather, the rule makes more zero-emission options available across the state for entities that choose them. Colorado incorporated the California Air Resource Board’s Advanced Clean Trucks Rule by reference to create a market-based approach for promoting clean trucks.

Truck and engine manufacturers that produce on-road vehicles with over 8,500 pounds gross vehicle weight rating for sale in Colorado must submit annual sales reports through California Air Resource Board’s Advanced Clean Trucks reporting system. Reports must be completed no later than 90 days following the end of each model year. The rule allows manufacturers to earn optional early action credits if they choose to submit reports for the model years 2024-2026. Then, the rule requires manufacturers to submit reports starting with model year 2027.

Auto manufacturers will accrue annual deficits based on the number of medium and heavy-duty vehicles delivered for sale in Colorado. The rule requires manufacturers to balance those deficits by generating zero-emission vehicle credits starting in the model year 2027.


The Heavy-Duty Low Nitrogen Oxides (NOx) Rule

The Heavy-Duty Low Nitrogen Oxides (NOx) Rule requires heavy-duty vehicle manufacturers to make cleaner vehicles, improve how they test vehicle engines and extend engine warranties. NOx is formed whenever fuel is burned, including operating vehicles that run on gas or diesel. NOx can form harmful ground-level ozone when it mixes with other air pollutants in heat and sunlight. Starting in model year 2027, this rule will reduce NOx emissions per new vehicle sold by 90% below current standards.

The rule applies to vehicles offered for sale or lease in Colorado with a gross vehicle weight rating of 14,001 pounds or greater in model year 2027 and subsequent model years. Certain transit buses and emergency vehicles are exempt. 

Automakers can submit their annual vehicle sales reports via email to cdphe_colevzev@state.co.us.


The Large Entity Reporting Rule

Colorado’s Large Entity Reporting Rule went into effect in June 2023. The revision added the Large Entity Reporting regulation to Regulation 20, Part G. Large Entity Reporting requires entities with fleets of 20 or more vehicles with a gross vehicle weight rating greater than 8,500 pounds to report fleet information to the Air Pollution Control Division. The reporting requirement is to assess the suitability of zero-emission vehicles in multiple use cases and inform future strategies for the zero-emission vehicles market in Colorado.

The rule requires fleets to submit information twice. Applicable entities must submit their reports by November 30, 2024, and December 31, 2027.

The division will make a reporting template and guidance documentation available in September 2024

If you have difficulties accessing or completing the template or any other questions regarding Large Entity Reporting, contact cdphe_apcd_ler@state.co.us .

Webinars in summer 2024:
The division planned two webinars for summer 2024 to discuss:

  • General information about Large Entity Reporting.
  • How to fill out the Large Entity Reporting spreadsheet.
  • Questions and answers.

The information will be the same for both webinars.


Past public sessions

The division held two public listening sessions to gather public input on Colorado's clean truck rules:

Public listening session 1: September 7, 2022

Public listening session 2: October 22, 2022

The division also held public informational sessions to share general information on low- and zero-emission vehicles:

Public informational session 1: June 29, 2022

  • Traffic is an Equity Issue: How Traffic Harms Certain Communities More than Others and How Clean Trucking Policies Can Help. Dr. James Crooks is a scientist at National Jewish Health in Denver, where he researches how air quality and climate extremes affect human health. 
  • Recordings: English | Spanish
  • Presentation

Public informational session 2: May 12, 2022

  • LEV, ZEV - What Does It All Mean? An Introduction to the Different Types of Zero-Emission Vehicle Technologies and Hope They Offer For the Climate Crisis
  • Recordings: English | Spanish
  • Presentation

Public informational session 3: April 14, 2022

  • Cleaner Trucks are Vital for Better Air and the Climate: An Introduction to the Basics of the Colorado Clean Trucking Strategy and Why You Should Care
  • Recordings: English | Spanish
  • Presentation