If you’re driving north from Los Angeles, hitting that steep climb on the 118 freeway through the Santa Susana Pass, you feel like you’re still in the city. The traffic is there. The radio stations are the same. But once you crest that hill and the valley opens up in front of you, everything shifts. People always ask what county is Simi Valley in because, honestly, the geography is a total head trip.
Simi Valley is located in Ventura County, California.
It sits right on the jagged edge. It’s the southeastern corner of the county, tucked away behind a wall of sandstone boulders. To most people living in the San Fernando Valley, Simi just feels like another suburb of LA. It isn’t. That distinction matters for everything from who picks up your trash to how much you pay in sales tax.
Why Everyone Gets the County Wrong
The confusion isn't just you being bad at maps. Simi Valley is basically the gateway between two very different worlds.
On one side, you have the sprawling, infinite pavement of Los Angeles County. On the other, the slightly slower, windier, and more rugged terrain of Ventura County. Because so many people commute from Simi into the "Valley" (the San Fernando Valley) or over the hill into Hollywood and Burbank, the lines get blurred. Most of the 126,000 people living here spend their workdays in LA County but sleep in Ventura County.
You’ve got the 818 area code bleeding over. You’ve got the shared mountain ranges. It’s easy to see why people lose track of the border. But the moment you cross that pass, you’re under the jurisdiction of the Ventura County Sheriff’s Office, not the LAPD or LASD.
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The Santa Susana Pass: The Great Divider
The Santa Susana Pass is the literal physical barrier that defines what county Simi Valley is in. It’s a messy, beautiful pile of rocks that has appeared in a thousand western movies. Historically, this pass was a nightmare for stagecoaches. Today, it’s a bottleneck for commuters.
Geologically, it acts as a cork. It keeps the coastal air of Ventura County from mixing too easily with the trapped heat of the San Fernando Valley. If you’re a local, you know the "Simi winds." Those Santa Ana winds roar through this corridor, reminding everyone exactly where the mountain breaks are.
The Politics of Being in Ventura County
Being in Ventura County isn’t just a trivia fact. It changes the vibe of the city. Ventura County has historically been more conservative than its neighbor to the east, though that’s shifting a bit lately.
The city is famous—or infamous, depending on who you ask—for the 1992 Rodney King trial. That trial was moved to Simi Valley specifically because it was in a different county with a different jury pool. That single event inextricably linked the question of what county is Simi Valley in to a massive moment in American civil rights history. It highlighted the perceived cultural gap between the "blue" urban core of Los Angeles and the "redder" suburban feel of Ventura County.
The Ronald Reagan Legacy
You can’t talk about this place without mentioning the Ronald Reagan Presidential Library. It sits on a hill overlooking the valley. It’s arguably the most famous landmark in the entire county.
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The library isn’t just a museum; it’s the spiritual center of the city. It’s where world leaders have gathered. It’s where the Air Force One that served seven presidents is parked inside a giant glass hangar. If Simi Valley were in LA County, the Library would feel like just another tourist stop. In Ventura County, it feels like the crown jewel.
Life on the Edge: Practical Differences
If you’re thinking about moving here or just visiting, the county line affects your wallet and your weekend.
- Sales Tax: It’s usually lower here than in the heart of LA. People will literally drive over the pass just to buy a car or a big-screen TV because those percentage points add up.
- Schools: Simi Valley Unified is its own beast. It operates under the Ventura County Office of Education.
- Crime Rates: Simi has a reputation for being one of the safest cities in America for its size. Locals often attribute this to the "Ventura County way" of law enforcement, which tends to be very proactive compared to the overwhelmed systems in Los Angeles.
It’s a "bedroom community." That’s the term real estate agents love. It means you work somewhere else, but you come here to hide. The hills are full of mountain bikers and hikers who want to disappear into the Long Canyon or Rocky Peak trails. You don't get that kind of immediate access to wilderness in the middle of LA.
The Film History You Didn't Know
Because it's so close to the studios but technically in a different county with different landscapes, Simi has been a Hollywood darling for a century.
Remember Poltergeist? That was filmed in a neighborhood here. The house is still there, though it looks a lot less haunted now. Little House on the Prairie was filmed at Big Sky Ranch. When you see those rolling hills and think, "That looks like the Old West," you’re looking at Ventura County’s specific brand of oak-studded golden hills.
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Getting Around and Staying Put
The Metrolink Ventura County Line stops right in the middle of town. It’s a lifeline. It connects the quiet suburbs of Simi to Union Station in downtown LA.
But here is the thing: people who live here really stay here. There’s a sense of pride in not being part of the LA sprawl. They like the fact that when they tell people what county Simi Valley is in, they get to claim the "V.C." lifestyle. It’s a bit more relaxed. A bit more space. A lot more rocks.
Honestly, the best way to understand the county divide is to look at the hills. In LA, the hills are covered in houses and fences. In Simi, the hills are mostly still wild. That’s the Ventura County influence. They have much stricter open-space laws (look up SOAR initiatives if you want to get nerdy about land use). This keeps the valley from turning into one giant parking lot.
How to Verify the Border Yourself
If you’re still confused while driving, look at the signs.
- Check the Freeway Signs: When you're on the 118 West, look for the "Ventura County Line" sign right as you hit the top of the Santa Susana Pass.
- Look at the Police Cars: LAPD cars are black and white. Ventura County Sheriff vehicles have a very distinct green and white color scheme.
- The ZIP Codes: Simi Valley uses 93062, 93063, 93065, and 93094. LA codes usually start with 90 or 91.
Actionable Next Steps for Visitors or Residents
- Visit the Reagan Library: Even if you aren't into politics, the view from the South Lawn is the best way to see the entire valley and understand its geography.
- Hike Rocky Peak: This trail sits right on the county line. You can literally stand with one foot in Los Angeles County and one foot in Ventura County. It’s a steep climb, but the 360-degree views are insane.
- Check the Sales Tax: Before making a major purchase, compare the rate in Simi Valley to nearby Chatsworth or Northridge. You might save a few hundred bucks just by driving ten minutes west.
- Explore the Corriganville Movie Ranch: This is a public park now. It used to be a massive filming site. It’s the perfect place to see the rugged terrain that makes this county unique.
Understanding the geography of this area helps you navigate the weird social and political layers of Southern California. Simi Valley isn't just a suburb; it's a specific choice to live on the other side of the mountain.