Last updated: February 2026
That sinking feeling when you realize your Mercedes key is gone, damaged, or locked inside your car is rough. We get it. Stuart Locksmiths provides Mercedes key replacement in Stuart, FL for all models and key types, including smart keys, key fobs, and older cut keys. Service typically runs $185 to $425 depending on your model and key type, and our mobile tech can reach most Stuart locations within 25 minutes. No tow truck. No dealership appointment. Just a licensed locksmith at your window with the right equipment to get you moving.
Why Mercedes Keys Are a Different Animal
Mercedes-Benz uses some of the most advanced key technology in the automotive world. Since the mid-2000s, Mercedes has used encrypted transponder chips, and newer models use KESSY (Keyless Start System) proximity keys that communicate with the car's ECU on a rolling code system.
That means a generic key blank won't work. Ever. The replacement key has to be cut to your exact blade profile AND programmed to your specific vehicle identification number. If the programming fails or uses the wrong software protocol, you could accidentally lock out your ECU entirely.
That's why we specifically train for Mercedes systems. Our equipment includes current OBD-II diagnostic interfaces that support Mercedes-Benz SCN coding, which is the same infrastructure required to code smart keys on C-Class, E-Class, GLE, and Sprinter vehicles.
Mercedes Key Replacement Pricing in Stuart
Dealer pricing on Mercedes keys has gotten out of hand. A dealership in Palm Beach or Fort Pierce will quote you $400 to $800 just for the key, not counting the $150+ diagnostic fee and a 3 to 7 day wait for parts. We stock the most common Mercedes key shells and blank transponder units locally, which keeps costs down significantly.
| Key Type | Models (Examples) | Stuart Locksmiths Price | Dealer Estimate |
|---|---|---|---|
| Standard Transponder Key | 2001-2008 C, E, ML-Class | $185 - $235 | $350 - $500 |
| Remote Head Key (Flip Key) | 2008-2015 GLK, SLK, CLS | $220 - $295 | $450 - $600 |
| KESSY Proximity Smart Key | 2016+ GLE, GLC, E-Class, S-Class | $295 - $425 | $600 - $900 |
| Sprinter Van Key | All Sprinter generations | $240 - $350 | $500 - $750 |
All prices include cutting, programming, and a function test before we leave. No surprise charges. (Source: ALOA Pricing Survey 2024 and local dealer service department quotes, Martin County FL)
How Our Mercedes Key Replacement Works
- Call us at (772) 362-5731. Tell us your year, model, and whether you have any working keys left. That last part matters a lot for Mercedes systems.
- We verify ownership on-site. We'll need your registration and a photo ID. This protects you as much as anyone. Non-negotiable for our license compliance.
- VIN lookup and key code retrieval. We pull your key cut data from the vehicle's VIN. On some older models, we read the lock cylinder directly.
- Key cutting. We cut the blade on our mobile key machine to your exact specifications.
- Programming and pairing. We connect to your OBD-II port, run the Mercedes coding sequence, and pair the new transponder or smart key to your ECU. This takes 12 to 20 minutes depending on the model.
Done. Start the car. Test every function. You're on your way.
Stuart's Heat and Sand Are Killing Your Mercedes Keys Faster Than You Think
South Florida's climate is brutal on electronics. The UV exposure on the Treasure Coast, combined with humidity off the St. Lucie River and salt air from the Stuart waterfront, degrades key fob batteries and circuit boards faster than anywhere in the northern US.
We see a lot of Mercedes owners in Stuart whose smart keys fail gradually: first the range drops, then the keyless entry gets spotty, then the car won't start at all. It's not the car. It's the key. A key that's been sitting in the sun on your boat at the Stuart Municipal Marina or baking in a cup holder on US-1 is on borrowed time.
If your key isn't dead yet but acting up, call us before you're stranded on Kanner Highway at 8 PM. A battery swap plus signal test costs almost nothing compared to an emergency replacement call.
We also serve Palm City, Jensen Beach, and Port St. Lucie with the same mobile response.
Why Choose Stuart Locksmiths for Your Mercedes
- Licensed and insured in Florida. Florida requires automotive locksmiths to carry a Class BB license. Ours is current. Ask to see it on arrival.
- Mercedes-specific tooling. We use Autel and AVDI platforms with active Mercedes subscriptions, not cheap cloner boxes that brick ECUs.
- Mobile service to all of Stuart. Downtown Stuart, Sailfish Point, North River Shores, Rocky Point, we come to you.
- No tow fee. The dealership route almost always means towing. We eliminate that $75 to $150 cost entirely.
- Same-day service. We don't order parts and call you back in a week. Most Mercedes replacements are done the same day, often within an hour of your call.
- Honest quotes up front. We give you a firm number before we start. The price you hear on the phone is the price on the invoice.
We also handle car lockout service if your key is inside the vehicle, and key fob programming if you just need to pair a replacement remote to an existing working key.
Need help with other vehicles in the household? We also cover BMW key replacement and transponder key programming for most European makes.
Frequently Asked Questions
Can you replace a Mercedes smart key without the original key present?
Yes. This is called an "all-keys-lost" scenario. It requires additional steps to clear the existing key codes from the ECU before new keys can be programmed. It takes longer, typically 45 to 75 minutes, and costs slightly more, but it's fully possible without the original.
How much does Mercedes-Benz key replacement cost in Stuart, FL?
Expect $185 to $425 depending on your model and key type. Older transponder keys for pre-2010 models are on the lower end. KESSY proximity keys for 2016 and newer models are on the higher end. We give firm quotes before we start.
Will a locksmith-programmed Mercedes key work the same as a dealer key?
Yes. The programming is done through the same OBD-II interface and Mercedes coding protocols a dealer uses. The key is functionally identical. The only difference is price and wait time.
How long does Mercedes key replacement take?
For most models, 20 to 40 minutes once our tech is on-site. All-keys-lost jobs take 45 to 75 minutes. We'll give you an honest time estimate when you call based on your specific vehicle.
What Mercedes models can you program keys for?
We handle all common Mercedes-Benz passenger vehicles: A, B, C, CLA, CLS, E, GLA, GLB, GLC, GLE, GLS, S-Class, SLK, SLC, and AMG variants. We also do Sprinter vans. If you have an unusual or very new model, call us and we'll confirm before you wait on a tech.
My Mercedes says "Key Not Found" but the key is right there. What's happening?
Usually a dead key fob battery, a damaged transponder chip, or a key that's been demagnetized. Sometimes it's a failing key reader antenna in the steering column. Call us for a diagnosis. The fix might be as simple as a $6 battery or as involved as a full key replacement.
Do I need to go to a Mercedes dealership to get a replacement key?
No. A licensed automotive locksmith with the right equipment can replace and program your Mercedes key. Stuart Locksmiths is licensed under Florida's Class BB automotive locksmith requirements and carries Mercedes-compatible programming tools.
What proof of ownership do I need?
Your current vehicle registration and a valid government-issued photo ID. Both must match or we can't legally complete the service. This protects vehicle owners from unauthorized key duplication.
Can you come to my location in Stuart, or do I have to bring the car somewhere?
We come to you. Our mobile unit is stocked for Mercedes jobs. Whether you're at Harbour Bay, off SE Ocean Boulevard, or near the Stuart airport on Witham Field, we'll find you.
My Mercedes key fob works but the blade is broken. Can you just replace the blade?
Often, yes. If the existing transponder chip is intact, we may be able to transfer it to a new shell and cut a new blade without full reprogramming. That drops the cost considerably. Bring the damaged key when you call.
Is it cheaper to get a Mercedes key replacement from a locksmith or the dealer?
Locksmith is almost always cheaper. Dealers charge $400 to $900 for the same key plus a diagnostic fee. They also typically need 3 to 7 days to order the key. We do it same day for $185 to $425 total, including programming.
Do you offer Mercedes key replacement after hours in Stuart?
Yes. We provide emergency locksmith service for Stuart and surrounding Martin County communities. After-hours calls may include a service fee, which we'll tell you upfront when you call.
Locked out or need a replacement Mercedes key in Stuart right now? Call Stuart Locksmiths at (772) 362-5731. We'll give you a firm quote in 60 seconds and have a tech headed your way fast.