This guide explains how the Clean Air Vehicle (CAV) decal program works in California, how to apply, what it lets you do, and what changes on October 1, 2025. You’ll also learn what to expect for HOV lane access, enforcement, and key rules for EV drivers.


Why this matters for EV owners

Imagine you bought an electric vehicle (EV) and you’ve been driving in the carpool lanes. Now picture getting pulled over—or getting charged a toll—because your decal is missing, expired, or not valid anymore.

That’s the core problem drivers are trying to avoid: the CAV decal was a simple way to prove eligibility for solo HOV access and sometimes reduced toll rates. But the federal program ended, and the rules changed quickly.


Big update from the California DMV

California DMV says the federal government ended the CAV decal program.

Key dates you need to know

Item Date
DMV stopped accepting new CAV decal applications August 29, 2025
CAV decals stop being valid October 1, 2025
Federal authorization expires September 30, 2025
How long decals were typically valid under the old federal rule Up to 4 years
Example expiration rule DMV described Expires on January 1 of the fourth year after issue

DMV warning: Starting October 1, 2025, vehicles displaying a CAV decal are not allowed to use carpool HOV lanes with a single occupant and won’t get reduced toll rates (where those reductions applied). Drivers must follow posted vehicle occupancy requirements.

DMV also states: CAV decals were good for up to four years, but all decals become invalid on October 1, 2025 regardless of issue date.


The two month grace period for HOV lane access

From the EV-owner discussions, there’s a practical “grace” idea around the switch to stricter enforcement.

What people should expect during the grace period

  • It is still illegal to drive solo in carpool lanes with an expired clean air sticker / decal after the cutoff.
  • Law enforcement may choose an education warning approach during the grace period instead of immediately issuing a ticket.
  • Violations may still show up in the system, including tolls/penalties captured by carpool enforcement cameras, depending on the situation described.

Bottom line: Don’t treat the grace period as “safe to keep using the lane.” The message from owners is that the point is to stop relying on the decal-based solo rule.


What CHP enforcement can look like

When enforcement starts after the grace period, drivers without valid proof should expect normal enforcement actions.

Practical enforcement scenarios

Situation What could happen
Decal is expired or not valid after Oct 1, 2025 Driver can receive a citation for violating occupancy rules
Driver has a decal that is not valid for current rules Treated like the driver doesn’t have the required status
During the grace window Officers may issue warnings/education instead of tickets (not guaranteed)

Also, DMV specifically says that after the program ends, drivers must meet posted occupancy rules or risk a citation.


Which lanes are covered

Owners discussing the topic generally treat the “sticker required for solo” concept as mainly about HOV/carpool solo eligibility.

Competitor discussion suggests the two-month grace concept is focused on HFOV carpool lanes where stickers were used to allow solo drivers.

Quick way to think about it

  • If the route uses carpool lane rules that depend on CAV status, the grace period affects how strictly it’s enforced early on.
  • Paid express lanes (example often mentioned is I-15) have their own toll rules, and you should not assume the decal changes toll eligibility after the program ends.

Because lane-by-lane rules vary, the safest rule is:
Follow posted occupancy/toll signage first.


Rules for solo HOV lane driving with an expired or absent CAV decal

After the federal end date, the program stops doing its job.

The rule in plain language

  • If you’re driving solo in carpool/HOV lanes, you must meet the current posted requirements.
  • If your decal is invalid (including after October 1, 2025), you should not expect solo access.

What penalties can mean

DMV’s statement is clear: drivers who violate the law may receive a citation.

And from EV-owner experience described in forums:
- You may still face toll or penalty consequences recorded by the enforcement systems.


Where to mount a FasTrak transponder in a Lucid Air

Lucid owners shared a specific mounting idea.

Example placement described by an owner

  • Mount it behind the cockpit display
  • The goal is:
  • Visible from outside (for FasTrak readers)
  • Not obvious from inside

This matches the practical question: “Where is the optimal location… so it works and is placed correctly?”


How to apply for Clean Air Vehicle decals in California

The application process is tied to the DMV program.

What DMV says the CAV decal does

DMV describes the CAV decal and CAV decal ID card as allowing single occupancy use of HOV (carpool) lanes for qualifying vehicles.

Requirements basics from the available materials

A forum guide (based on DMV form REG 1000) indicates you generally need:
- Your vehicle registration (or documentation for the vehicle)
- Completed application form REG 1000
- Payment for the program fee

The key “prove eligibility” point is that it’s the decal (not just the fact you own an electric vehicle) that matters for the prior HOV/toll benefits.


Where the program application and documents fit

Here’s the “typical” checklist pattern described:

Step What you do Example detail mentioned
1 Confirm eligibility Vehicle must meet emissions standards and criteria
2 Wait for correct timing Program is no longer accepting new applications after Aug 29, 2025
3 Complete DMV form REG 1000
4 Include required items Vehicle registration + other proof
5 Pay Fee by check/money order or online (card fee noted in the forum guide)
6 Submit and wait Processing described as about 2 weeks in the forum guide

Cost to obtain a CAV decal

A guide derived from the DMV application form process states:
- $27 (paid by check/money order or online)
- Credit card payments may include a 1.95% fee

(Exact costs can change; the program also stopped accepting new applications on Aug 29, 2025.)


Where to place the CAV decal on a Tesla

One forum answer summarizes DMV guidance:

  • The CAV decal must be affixed in the location specified by DMV
  • Usually described as on the rear quarter panels
  • Do not place it inside the window or on the dashboard if you want it to qualify

Placement rule in plain language

If it can’t be seen by enforcement and toll readers from the outside, it may not count.


Can you display the decal inside the car

No, based on the guidance in the available text:
- Placing it inside (window/dashboard) is not allowed for HOV/toll benefits and may lead to citation risk.


Who to contact for help

DMV is the main contact point.
The available material also mentions:
- Using DMV contact channels and assistance for the application process


Tesla as a clean air vehicle

For Tesla drivers specifically, the available materials describe:
- You apply through the DMV CAV decal process
- Having a Tesla alone is not enough to get solo carpool benefits; the decal must be issued and properly displayed when the program was active.

Also, one description emphasizes that decals determine eligibility—not the license plate by itself for those specific benefits.


Deadline and what happened after

Deadline and program end

  • DMV stopped accepting new CAV applications on August 29, 2025
  • All decals stop being valid October 1, 2025

How drivers are informed

DMV says:
- Offices display information about the end of the program
- A notice is posted on the DMV website
- DMV will directly notify customers with an email address on file
- Social media reminders will be used
- Caltrans will post electronic road signage reading “CLEAN AIR DECALS NOT VALID STARTING OCT 1”


What happens to invalid decals after expiration

DMV’s federal-program message is direct:
- Starting October 1, 2025, CAV decals are not valid
- You must follow posted occupancy rules
- Violating the law can lead to a citation


Quick history timeline

DMV also provides background:

Topic What DMV states
Original authorization for HOV single-occupant clean vehicles 1999
Most recent reauthorization before current program 2017
When DMV began issuing under the current program January 1, 2019
How long decals were typically valid before the federal change Up to 4 years (with the “expires January 1 of the fourth year after issue” example)

What the DMV recommends after the federal decision

DMV’s position described in the announcement:
- It calls the program a “great program” for climate-conscious drivers
- It says the federal end harms drivers
- It urges the federal government to retain the program
- But practically, DMV tells drivers the rules will change and occupancy rules must be followed


What you should do right now

Here’s a simple action plan based on the end of the program:

Situation Recommended action
You have a CAV decal Assume it will be invalid after Oct 1, 2025
You planned to rely on solo HOV access Stop relying on the decal-based rule; follow posted requirements
You’re checking whether the program is still taking apps Remember: DMV stopped accepting new applications on Aug 29, 2025
You need to understand toll/HOV eligibility Follow lane signage first, since decals won’t be valid after Oct 1

Summary you can remember

Topic Answer
How to get the CAV decal Apply through DMV using the program process (but new applications ended Aug 29, 2025)
When CAV decals stop working October 1, 2025
Can you still use HOV solo after that No, you must meet posted occupancy requirements
Can CHP issue warnings first During the grace period, education warnings may happen, but the violation is still real
Where to mount decals on a Tesla Must be affixed in the DMV-specified outside-visible location, not inside the car

Small visual map of the timeline

timeline
    title CAV decal program changes in California
    2019-01-01 : DMV begins issuing under current program
    2025-08-29 : DMV stops accepting new applications
    2025-09-30 : Federal authorization expires
    2025-10-01 : All CAV decals no longer valid

This is the practical reality behind “how to get clean air vehicle sticker” in 2025: the process is tightly linked to the DMV CAV program, and the most important change is that the program ended and decals stop being valid on October 1, 2025.