Lane‑Splitting in California: What Motorcyclists & Drivers Need to Know in 2025

Lane‑splitting remains one of the most misunderstood and legally complex practices on California’s roadways. For motorcyclists it can offer a traffic advantage—but it also carries risk. For drivers, a lane‑splitting rider introduces unique hazards and legal questions. Whether you ride a motorcycle or drive around one, you should know the law, how it applies in 2025, and what happens if a lane‑splitting crash occurs.

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What Is Lane‑Splitting Under California Law?

Under California Vehicle Code § 21658.1, added by Assembly Bill 51 and effective January 1, 2017, the practice of “lane‑splitting” is defined as a two‑wheeled motorcycle riding between rows of stopped or moving vehicles in the same lane, on either divided or undivided streets or highways.

This means California explicitly allows a motorcyclist to operate between lanes of traffic—something not clearly permitted in most other states. 

However, the statute does not specify fixed speed limits or lane locations—it requires the maneuver to be done in a “manner that is safe and prudent” under the circumstances.

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Why 2025 Matters: Key Updates and Trends

While the statute has not been radically changed in 2025, several trends make 2025 a crucial year to understand lane‑splitting:

• Insurance companies are increasingly scrutinizing lane‑splitting as a factor in motorcycle accidents and may use it to argue fault or reduced compensation.
  
• Safety guidelines from the California Highway Patrol (CHP) remain critical. While not legally binding, these guidelines on speed differential and road conditions are used in accident investigations and civil claims.
  
• California remains the only state that broadly allows full lane splitting. Other states are adopting more limited “lane filtering” laws, making California’s rules more relevant for riders and drivers traveling across state lines.
  

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How Riders Should Split Lanes Safely and Legally

Best Practices for Motorcyclists

• Stay within about 10 mph faster than the surrounding traffic flow—broader speed differentials significantly increase risk. 
• Avoid lane‑splitting when traffic is moving at high speeds or speeds are unpredictable (for example, > 30 mph) or in poor visibility.
• Choose lanes with wider spacing and fewer large vehicles where possible—splitting between big rigs or in narrow lanes heightens danger. California Highway Patrol
• Wear bright or reflective gear and stay visible, avoid riding on the shoulder (which is illegal and not lane‑splitting). The Zebra
  

Responsibilities for Drivers

• Understand that lane‑splitting is legal—and intentionally blocking or obstructing a motorcyclist may violate law.
• Always check blind spots, give space when a motorcycle is passing left, and avoid opening a door into a motorcyclist’s path.
• Anticipate lane‑splitting in heavy traffic and behave accordingly—slow down, maintain awareness, and avoid sudden lane changes.

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If a Lane‑Splitting Accident Happens: Legal Implications for Riders & Drivers

For Riders

Even though lane‑splitting is legal, if you are involved in a collision while doing so, insurers and defense attorneys will scrutinize whether your maneuver was prudent. Common issues include: excessive speed compared to surrounding traffic, splitting in fast‑moving flow, or splitting near a merging vehicle.

Because California uses a pure comparative‑fault system, you can still recover compensation even if you bear some fault—but your recovery will be reduced accordingly. 

For Drivers

If you are involved in a crash with a motorcyclist who was splitting lanes legally, you cannot assume their actions automatically excuse your negligence. Drivers have duties too: safe lane changes, avoiding negligence, respecting motorcyclists’ rights—and blocking or impeding a motorcyclist may increase your liability.

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Common Injuries and Claim Issues

Motorcycle accidents involving lane‑splitting can lead to severe injuries—even at lower speeds—because motorcycles lack the protective structures of cars. Injuries may include:

• Road rash, severe abrasions, fractures
• Head injuries (even with helmets), spinal injury, traumatic brain injury
• Long‑term pain, disability, lost earning capacity

Insurance claim issues to watch:

• Was lane‑splitting a factor that reduced value?
• Did the driver change lanes or open a door into the path?
• Was evidence preserved (dash‑cam, phone footage, witness statements)?
  

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Why You Should Talk to a Motorcycle Accident Lawyer Now

If you’ve been injured in a lane‑splitting accident—or you were driving and hit a lane‑splitting motorcyclist—time matters. Evidence can be lost, video erased, and lane conditions change quickly. A lawyer experienced with motorcycle, lane‑splitting and comparative‑fault cases can:

• Secure electronic evidence (surveillance, phone footage, telematics)
• Analyze vehicle speeds, roadway conditions, liability for both rider and driver
• Navigate the insurance companies’ attempts to shift fault due to lane‑splitting
• Work to maximize your recovery based on your injuries, medical care, lost wages, pain and suffering

At Phillips & Pelly, we have the experience and dedication to handle lane‑splitting cases in San Diego and across California. Reach out for a free, no‑obligation consultation.