December in California is a runner's dream. While the rest of the country is layering up in thermal gear and dodging ice patches, California offers crisp, cool mornings and clear skies perfect for logging 13.1 miles. Whether you are chasing a late-season personal best or just looking for a festive way to close out your racing year, you will find 41 half marathons in California in December to choose from. The terrain varies from flat coastal roads to rolling city streets, giving both first-timers and experienced runners plenty of options. From the foggy, scenic mornings of San Francisco to the sun-drenched finish lines in San Diego, this month is all about celebrating the miles you have put in all year. Let's look at some of the standout races to help you find your next adventure.
San Diego Holiday Half Marathon & 5K
If you are looking for a fast course to close out your year, the San Diego Holiday Half Marathon & 5K is a Runner Favorite that delivers. Taking place on December 19, 2026, this race offers a rolling road route that is known for being quick. The course starts on Penasquitos Drive in front of the Hotel Karlan and makes its way southwest. You will face your only real hill early on at mile 1.5 along Carmel Mountain Road, which means the rest of the race is about settling into a good rhythm and enjoying the ride. After that early climb, you get to cruise along the 56 bike path. This is a fantastic option for first-timers who want to get the hard work out of the way early, as well as experienced runners looking to test their late-season fitness. The San Diego weather in December is usually ideal for running, making this a great destination race if you want to pair your 13.1 miles with a weekend getaway.
Sunrise Marathon 5K/10K/13.1 SAN FRANCISCO
There is something uniquely special about starting a race just as the sun comes up, and the Sunrise Marathon 5K/10K/13.1 SAN FRANCISCO captures that magic perfectly. Scheduled for December 12, 2026, this Runner Favorite offers a flat road course that is incredibly welcoming for anyone tackling their first half marathon. The early start rewards you with breathtaking views of the Bay Area as the morning light hits the water. Because the course is flat, you do not have to worry about the intimidating hills San Francisco is famous for. Instead, you can focus on the scenery and the shared energy of the runners around you. The organizers keep the waves small and they sell out quickly, which creates an intimate, community-focused feel rather than a massive, overwhelming crowd. If you want a peaceful but energizing race experience that leaves the rest of your Saturday open for exploring the city, this is a beautiful way to earn your finisher medal.
Santa To The Sea 1/2 Marathon, 1/4 Marathon & 5K
Running is always better when it supports a good cause, and the Santa To The Sea 1/2 Marathon, 1/4 Marathon & 5K in Oxnard brings a massive dose of holiday spirit to the starting line. Taking place on December 12, 2026, this flat road race is a Runner Favorite with a rich community history. It started back in 2003 as a toy drive to celebrate moving the world's largest Santa Claus statue, and it has since grown into a beloved annual running tradition. The flat terrain makes it highly approachable for runners of all levels, so if you are nervous about your first half marathon, this course is gentle and forgiving. Beyond the miles, the focus here is on giving back, with the event continuing its legacy as a toy drive for local children. It is the kind of race where the miles feel a little lighter because of the joyful, community-centered atmosphere surrounding the entire morning.
Sunrise Marathon 5K/10K/13.1 LOS ANGELES
If you love the idea of an early morning race but prefer Southern California, the Sunrise Marathon 5K/10K/13.1 LOS ANGELES is a fantastic Standout option. Also held on December 12, 2026, this event mirrors its San Francisco counterpart by offering a beautiful, scenic start to your day. The road course is flat, making it an excellent choice for runners who want a steady, predictable route without any surprise elevation changes. Taking on a half marathon in Los Angeles during December means you get to avoid the intense heat of the summer months, enjoying cool, comfortable miles instead. Like the northern version of this race, waves are capped and fill up fast, ensuring a supportive and uncrowded environment. It is a great pick for first-timers who want a low-stress race day, or veterans looking for a well-organized, straightforward run to test their pacing before the year ends.
Santa Hustle Roseville
Sometimes you do not want to worry about your finish time—you just want to have a great time. The Santa Hustle Roseville on December 13, 2026, is built entirely around holiday fun. This Solid Pick is a flat road race that welcomes runners of all ages and abilities, making it one of the most approachable half marathons of the season. The Santa Hustle series is famous for its winter wonderland atmosphere, complete with festive music, holiday cheer, and plenty of runners decked out in Santa gear. If you are training for your first half marathon and feeling a little intimidated by the distance, a race like this is the perfect antidote. The flat course is easy to navigate, and the joyful distractions along the way will keep your mind off your tired legs. It is a wonderful way to celebrate your training journey with a community that is focused on smiles rather than speed.
Holly Jolly Marathon
Rounding out the festive options in Southern California is the Holly Jolly Marathon in Camarillo. Scheduled for December 20, 2026, this road race is a Solid Pick for runners looking to squeeze in one last half marathon right before the holidays. Camarillo offers a relaxed, welcoming environment that is ideal for a low-pressure race day. Without the massive crowds of some of the bigger city races, you can focus on running your own race at your own pace. Whether you are using this as a fun training run to maintain your fitness through the winter, or you are stepping up to the 13.1 distance for the very first time, the supportive atmosphere will help carry you to the finish line. It is a great excuse to get outside, enjoy the crisp December air, and earn a medal before the holiday festivities fully take over your calendar.
How to Choose Your December Half Marathon
With 41 half marathons in California in December, narrowing down your options comes down to what kind of experience you want. If you are aiming for a fast finish or want to get your climbing done early, the rolling route in San Diego is a fantastic choice. If you prefer a flat, scenic, and quiet morning, look toward the Sunrise events in San Francisco or Los Angeles. For runners who want to lean fully into the holiday spirit, the Santa to the Sea or Santa Hustle races offer flat courses paired with a lot of joy and community goodwill. Remember, whether this is your first half marathon or you are adding another state to your long-term journey, the best race is the one that gets you excited to train. Pick a destination that sounds fun, grab a friend to run with, and enjoy the miles. You can explore all California half marathons to find the perfect fit for your next adventure.