Is the 5 a Freeway or a Highway?

Both: “the 5” refers to Interstate 5 (I-5), which is an Interstate Highway built to freeway standards—meaning it’s a controlled-access roadway with no at-grade intersections. In California, people commonly call it “the 5 freeway,” while in Oregon and Washington it’s more often called “I-5.” I-5 runs the length of the U.S. West Coast from the Mexican border at San Ysidro, California, to the Canadian border at Blaine, Washington.

What “freeway” and “highway” mean

To understand why I-5 is called both, it helps to clarify the difference between “freeway” and “highway,” and where “Interstate” fits in. The terms overlap, but each has a specific meaning in road design and everyday usage.

• Highway: A general term for a major public road. It can be anything from a rural two-lane route to a multi-lane corridor.
• Interstate Highway: Part of the federally designated Interstate Highway System (e.g., I-5). Interstates are numbered, signed with red-white-blue shields, and built to high standards for long-distance travel.
• Freeway: A type of highway with full control of access—on- and off-ramps instead of driveways, no cross-traffic, and grade-separated interchanges.
• Expressway: Similar to a freeway but may have some at-grade intersections or driveways; standards can vary by state.
• State Route: A highway designated and maintained by a state (e.g., California SR-1); some are freeways, others are not.

In short, a freeway is a specific kind of highway, and I-5 is both an Interstate Highway and, functionally, a freeway along its route.

How people refer to I-5 in different places

Regional language and local naming traditions influence whether people say “the 5,” “I-5,” or use a segment’s local name. Here’s how usage typically breaks down along the corridor.

1. California: The common phrasing is “the 5,” and in urban areas it’s widely called “the 5 freeway.” Several stretches also have historic/local names, such as the Golden State Freeway (through much of Los Angeles) and the Santa Ana Freeway (from Los Angeles into Orange County).
2. Oregon and Washington: People usually say “I-5.” The definite article (“the 5”) is rarely used in casual speech compared with Southern California.

These linguistic habits don’t change the road’s function; they just reflect regional preferences in how people talk about the same Interstate.

Why I-5 qualifies as a freeway

I-5 is designed and operated to Interstate freeway standards for most, if not all, of its length, providing uninterrupted, controlled-access travel across three states.

• Controlled access: Entry and exit are via ramps; there are no driveways or direct property connections.
• Grade separation: Cross streets pass over or under the roadway—no stoplights or cross traffic on the mainline.
• Medians and barriers: Divided carriageways typically separated by medians or barriers to improve safety.
• Design speeds: Built for higher, consistent speeds appropriate to an Interstate facility.
• Limited interruptions: Rest areas and service interchanges are designed not to disrupt mainline flow.
• Auxiliary features: Many urban segments include carpool/HOV or express lanes, consistent with modern freeway operations.

These attributes meet the defining criteria of a freeway while also fulfilling the standards of the Interstate Highway System.

Naming and signage

Officially, the route is “Interstate 5” and is signed with the standard red-white-blue Interstate shield marked “5.” Depending on location, you may also see local names on guide signs—such as “Golden State Freeway” or “Santa Ana Freeway” in parts of Southern California—alongside the I-5 designation. Regardless of the local nickname, the roadway remains I-5 and functions as a freeway.

Summary

I-5 is both an Interstate Highway and, in practical terms, a freeway: a fully controlled-access route designed for uninterrupted travel. In California it’s commonly called “the 5” (often “the 5 freeway”); in Oregon and Washington, it’s typically “I-5.” The terminology differs, but the road is the same high-standard, limited-access corridor running from Mexico to Canada.

What is highway 5 called in California?

I-5 is known colloquially as “the 5” to Southern California residents and “5” to Northern California residents due to varieties in California English. I-5 also has several named portions: the John J. Montgomery Freeway, San Diego Freeway, Santa Ana Freeway, Golden State Freeway, and West Side Freeway.

What is a freeway vs highway?

A highway is a broad term for a main public road connecting towns or cities, which may have intersections, traffic lights, and direct property access. A freeway is a specific type of highway that provides fully controlled access, meaning it has no traffic lights, intersections, or direct property access, with all entry and exit managed exclusively by ramps and interchanges. In essence, all freeways are highways, but not all highways are freeways.
 
Highway 

• Definition: A general term for any major public road connecting different areas, such as towns and cities.
• Features: Can include intersections, stoplights, pedestrian crossings, direct access to properties or businesses, and may vary in size from two lanes to multi-lane roads.
• Purpose: To provide a route between locations, serving both local and long-distance travel.

Freeway

• Definition: A highway with full control of access. 
• Features:
  • No intersections or traffic signals: Traffic is separated by medians, and cross-traffic uses overpasses or underpasses. 
  • Ramps: Entry and exit are managed solely through ramps and interchanges. 
  • High speed: Designed for high-speed, uninterrupted travel to ensure speed and efficiency. 
• Purpose: To facilitate high-speed, high-volume, long-distance travel with maximum efficiency and safety. 

The Relationship

• A freeway is a modern design concept for a highway. 
• You can think of a highway as the broad category, and a freeway as a specialized version within that category, like a specialized type of car within the broader category of vehicles. 

Regional Terminology 

• The terms can vary by region; for example, California residents commonly use “freeway,” while other parts of the U.S. might use “highway” or “expressway” for similar roads.

Is the I-5 the longest freeway?

Interstate 5 in California is the state’s primary north–south freeway and a key part of the West Coast’s transportation backbone. Stretching approximately 797 miles from the Mexican border in San Diego to the Oregon state line near Yreka, it is the longest Interstate highway within a single U.S. state.

Is I-5 a freeway or a highway?

Now named the West Side Freeway, I-5 travels northwest along the edge of the Central Valley through farmland and avoids populated areas. The freeway is connected to several of the valley’s main cities, including Fresno, Merced, and Modesto, by other highways.