You're driving up Highway 6, the engine is straining a bit against the Loveland Pass incline, and you realize you forgot the exact address of the condo. Or maybe you're trying to ship your skis ahead of time so you don't have to drag them through Denver International Airport. You go to type it in. You pause. Is it Keystone? Is it Dillon?
Basically, if you’re looking for the zip code for Keystone Colorado, the number you need is 80435.
But here is the thing: Keystone isn't actually a "town." Not in the legal sense, anyway. It's an unincorporated community. Because of that, the mail situation gets a little weird, and if you aren't careful, your Amazon package might end up sitting in a warehouse in Silverthorne while you're waiting for it at a lodge near River Run Village.
Why 80435 Covers So Much Ground
The 80435 zip code is a bit of a workhorse in Summit County. It doesn't just cover the ski resort. It handles the town of Dillon, the heights of Montezuma, and the sprawling base area of Keystone Resort.
When you look at a map, the lines are blurry. You might feel like you’re deep in the woods of Keystone, but your phone says you’re in Dillon. Honestly, that’s because the Dillon Post Office is the primary hub for this entire stretch of the Snake River Valley. If you’re sending a postcard from the top of North Peak at 11,660 feet, it’s going through the 80435 system.
It’s vast. We are talking about a zip code that scales thousands of vertical feet.
Most people don't realize that Montezuma—that tiny, quirky former mining town at the end of the road—also shares this zip. It's a rugged spot. No paved roads. No stoplights. Just a few dozen residents and a lot of snow. Yet, they share the same five digits as the luxury Hyatt Place at the base of the mountain.
The Logistics of Shipping to the Mountains
Shipping things to the zip code for Keystone Colorado is where the headaches start.
If you are staying at a managed property like those run by Vail Resorts or various independent management companies, you cannot just use 80435 and hope for the best. FedEx and UPS usually deliver to physical street addresses. That's fine. But the United States Postal Service (USPS) does not offer residential mail delivery in much of Keystone.
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Think about that.
If you live there full-time, you probably have a PO Box in Dillon. If you’re a visitor and you try to mail a letter to a physical condo address via USPS, it might get marked "undeliverable" and sent back to wherever it came from. It's a classic mountain town trap.
How to actually get your gear there
If you’re shipping luggage or skis, use a private carrier. UPS and FedEx know the layout of the resort. They know where the loading docks are for the Keystone Lodge & Spa. They understand that "Decatur Mountain Lodge" isn't just a name, but a specific spot they can access.
Always include the name of the resort or management company in the "Company" line of your shipping label. It helps the driver. A lot.
- Verify if your lodging allows guest packages. Some charge a "handling fee." It’s annoying, but it’s better than your gear being lost.
- Use the physical address: 21996 US-6, Keystone, CO 80435 is a common waypoint for the main resort area, but check your specific reservation.
- Avoid USPS for time-sensitive deliveries to the resort. Just don't do it.
The Identity Crisis: Keystone vs. Dillon
Keystone is a destination. Dillon is a municipality.
When you use the zip code for Keystone Colorado, you'll often see "Dillon, CO" auto-populate in the city field. Don't panic. You didn't type it in wrong. Because Keystone isn't incorporated, it technically falls under the Dillon postal umbrella.
Does it matter? Not really for your GPS. Google Maps knows where Keystone is. Apple Maps knows where Keystone is. But for legal documents or insurance forms, it can be a bit of a back-and-forth. Some systems won't recognize "Keystone" as a valid city name. If that happens, just switch it to Dillon. The 80435 code will ensure it gets to the right general vicinity.
Living the 80435 Life
Living in this zip code is a dream for some and a logistical puzzle for others. You’ve got the Keystone Lake, which is actually one of the largest outdoor groomed skating rinks in North America. Then you've got the three peaks—Decorum, North Peak, and the Outback.
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The geography is intense.
Snow removal is a constant battle in 80435. During a big cycle, the county and resort crews are working 24/7. If you're staying in the Mountain House base area or near the Snake River, you'll hear the "beep-beep-beep" of the plows at 3:00 AM. It’s the price you pay for fresh tracks at 8:30 AM.
Misconceptions about High Altitude Mail
A common myth is that there is a separate zip code for the "top" of the mountain. There isn't. Whether you are at the Alpenglow Stube (the highest AAA Four-Diamond dining experience in North America) or the convenience store in Lakeside Village, you are in 80435.
Another thing? People think the 970 area code is tied to the zip. It is, but 970 covers almost the entire Western Slope of Colorado. From Grand Junction to Steamboat. So while your zip is specific, your phone number is very broad.
Breaking Down the Neighborhoods
The zip code for Keystone Colorado encompasses several distinct "neighborhoods" that feel completely different from one another.
River Run Village is the heart of the action. It’s pedestrian-only. It’s where the gondola lives. If you’re staying here, your address will likely be 80435, but your car will be parked in a garage far away from your front door.
Lakeside Village is older, quieter, and centered around the ice rink. It’s got a more "70s ski vibe" in the best way possible. The buildings are sturdier, the units are often larger, and it feels a bit more like a community than a transit hub.
Then there is West Keystone. This is where you find the private homes and the quiet wooded lots. It’s further from the lifts but closer to the actual town of Dillon and the grocery stores. If you’re staying in a private home here, your 80435 mail delivery is even more precarious. Most of these homes have "clusters" of mailboxes at the end of the street, but again, USPS often won't deliver to them if they are considered "seasonal" or part of a specific resort tract.
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Why This Matters for Your Next Trip
Knowing the zip code for Keystone Colorado isn't just about trivia. It’s about ensuring your vacation goes smoothly.
If you are booking a rental car and the agency asks for your "destination zip code" to calculate taxes or local fees, 80435 is your number. If you are looking for local weather reports on an app that requires a zip, 80435 gives you the most accurate reading for the base of the mountain. Just remember that the temperature at the base (9,280 feet) is going to be about 10 degrees warmer than at the summit.
Technical specifics for the data-minded
- Primary City: Dillon, CO
- Acceptable City: Keystone, CO
- County: Summit County
- Time Zone: Mountain Standard Time (MST). We observe Daylight Saving Time.
- Elevation: Ranges from roughly 9,000 feet to over 12,000 feet within the zip boundaries.
Practical Steps for Travelers and Locals
If you are currently planning a trip or moving to the area, here is how you handle the 80435 logistics without losing your mind.
First, always verify your physical address through a mapping service before you arrive. Some condo complexes in Keystone have names that are very similar (e.g., Slopeside vs. Springs). Using the 80435 zip code with the wrong complex name is a recipe for a very long night of driving in circles.
Second, if you're a "digital nomad" trying to work from Keystone, check the internet providers. Most of the 80435 area is covered by Xfinity/Comcast or local high-speed fiber in newer developments, but the further you go toward Montezuma, the more likely you'll be relying on Starlink or spotty cellular data.
Third, for emergency services, always know your physical street address. If you call 911 from a cell phone, they can usually triangulate your position, but in the deep valleys of the Snake River, signals can bounce. Saying "I'm in 80435" isn't enough; knowing you're at "1234 Ida Belle Drive" saves lives.
Finally, keep a copy of your reservation on your phone offline. Cell service can be surprisingly patchy in the shadow of the mountains, even in a well-traveled zip code like this one.
When you're packing your bags or filling out those shipping labels, remember that 80435 is more than a number. It's a gateway to some of the best skiing in the world. Just don't expect the mailman to knock on your condo door. Use FedEx for your skis, use "Dillon" if "Keystone" fails on a form, and get ready for the thin air.
Check your shipping labels one last time. Ensure the physical address is prominent. If you’re using a PO Box, make sure it’s clearly labeled for the Dillon Post Office. Verified addresses prevent 90% of mountain travel headaches. Take a screenshot of your lodging's "Arrival Instructions" now, while you have clear Wi-Fi. It’s much easier than trying to load a PDF in a snowy parking lot at 9,000 feet.