Water damage is one of the most common and expensive homeowners insurance claims in California. A small leak behind a wall or under a sink can cause thousands of dollars in damage before anyone notices.
To help reduce water damage claims, Mercury Insurance has introduced a new water leak detection requirement for certain homeowners policies.
If you’re purchasing a new Mercury homeowners policy, here’s what you need to know.
Why Is Mercury Requiring Water Leak Detection Devices?
Water damage claims have become increasingly costly due to:
- Aging plumbing systems
- Burst pipes
- Water heater failures
- Washing machine hose leaks
- Refrigerator ice maker line leaks
- Toilet overflows
- Slab leaks
Many of these losses can go undetected for days or even weeks, resulting in major repairs and insurance claims.
By installing smart leak detection technology, homeowners can identify leaks early and potentially avoid significant damage.
When Does This New Requirement Take Effect?
The new requirement applies to:
New Mercury HO-3 Homeowners Policies effective May 29, 2026 and later.
The device does not necessarily need to be installed before the policy is issued. However, qualifying homes must have an approved leak detection device installed before the first renewal.
Which Homes Are Affected?
A water leak detection device will be required if the home meets any one of the following criteria:
1. Older Homes in High Water Risk Areas
- Home is 30 years old or older
- Located in a high non-weather water damage risk territory ( See Below)
2. High-Value Older Homes
- Home is 50 years old or older
- Coverage A (Dwelling Coverage) is $2 million or higher
3. Large Coverage Homes
- Home is 30 years old or older
- Coverage A is $2.5 million or higher
4. Luxury Homes
- Coverage A is $3 million or higher regardless of age
If your home falls into any of these categories, Mercury will require a qualifying leak detection system.
What Types of Water Leak Detection Devices Qualify?
Option 1: Whole Home Water Flow Monitoring
These systems continuously monitor water flow throughout the entire home.
Features include:
- Real-time water usage monitoring
- Leak detection alerts
- Smartphone notifications
- Monitoring of abnormal water activity
Popular examples include:
- Flo by Moen
- Phyn Plus
Option 2: Smart Leak Detection with Automatic Shutoff
This is the most advanced level of protection.
Benefits include:
- Detects leaks automatically
- Shuts off the water supply automatically
- Sends alerts to homeowners
- Helps prevent catastrophic water damage
Mercury requires this type of system for:
- Secondary homes
- Vacation homes
- Seasonal residences
- Homes with Coverage A of $2 million or more
If you’re not living in the home full-time, this option can provide valuable peace of mind.
Option 3: Smart Point-of-Leak Sensors
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These sensors are placed near common leak sources such as:
- Water heaters
- Toilets
- Washing machines
- Dishwashers
- Under sinks
When water touches the sensor, an alert is sent to the homeowner.
Mercury requires:
At least two more sensors than the total number of bathrooms in the home.
Examples:
| Bathrooms | Minimum Sensors Required |
|---|---|
| 1 Bathroom | 3 Sensors |
| 2 Bathrooms | 4 Sensors |
| 3 Bathrooms | 5 Sensors |
| 4 Bathrooms | 6 Sensors |
| 5 Bathrooms | 7 Sensors |
Can Homeowners Receive a Discount?
Yes.
In addition to helping prevent costly losses, Mercury may offer a homeowners insurance discount once a qualifying device is installed and verified.
Ask your insurance agent about available discounts and documentation requirements.
Is a Water Leak Detection System Worth It?
Absolutely.
Consider the cost of common water damage claims:
- Drywall repairs
- Flooring replacement
- Mold remediation
- Cabinet replacement
- Plumbing repairs
- Temporary housing expenses
A leak detection device costing a few hundred dollars can potentially prevent tens of thousands of dollars in damage.
Tips for California Homeowners
Even if Mercury doesn’t require a device for your home, consider installing one if:
- Your home is over 20 years old
- You travel frequently
- You own a vacation home
- Your plumbing system has never been updated
- Your home has experienced previous water damage
The earlier a leak is discovered, the less damage it typically causes.
Need Help Understanding Mercury’s New Requirement?
At Starwest Insurance Services, we help California homeowners understand changing insurance requirements and find the best coverage available.
Whether you’re purchasing a new homeowners policy, reviewing your current coverage, or trying to determine if your home qualifies for Mercury’s leak detection program, we’re here to help.
Contact James C.Q. Banh
📞 Office: 714-893-7271
📱 Cell/Text: 714-867-7799
Serving California homeowners since 1995 with no broker fees.
Starwest Insurance Services, LLC
Helping homeowners protect what matters most.
Homeowners can learn more directly from Mercury here:
Mercury Water Leak Detection Program:
https://www.mercuryinsurance.com/campaigns/leak-detection/
*High Non-Weather Water Risk Territories (Mercury Insurance)
ZIP codes subject to change by Mercury Insurance.
| ZIP Code | City |
|---|---|
| 90603 | Whittier |
| 90703 | Artesia |
| 90746 | Carson |
| 91042 | Tujunga |
| 91301 | Agoura |
| 91302 | Calabasas |
| 91311 | Chatsworth |
| 91320 | Dos Vientos Ranch |
| 91351 | Canyon Country |
| 91356 | Tarzana |
| 91364, 91367 | Woodland Hills |
| 91605 | North Hollywood |
| 91701 | Alta Loma |
| 91765 | Diamond Bar |
| 91786 | Upland |
| 91902 | Bonita |
| 91911 | Chula Vista |
| 91945 | Lemon Grove |
| 92009 | Carlsbad |
| 92020 | El Cajon |
| 92024 | Encinitas |
| 92025 | Escondido |
| 92040 | Lakeside |
| 92056, 92057 | Oceanside |
| 92078 | Elfin Forest |
| 92084 | Vista |
| 92115, 92117, 92119, 92120 | San Diego |
| 92313 | Grand Terrace |
| 92376 | Rialto |
| 92404 | Del Rosa |
| 92407 | Arrowhead Farms |
| 92503 | Arlington |
| 92504 | Casa Blanca |
| 92505 | La Sierra |
| 92509 | Jurupa Valley |
| 92530 | Lake Elsinore |
| 92543, 92544 | Hemet |
| 92551, 92553 | Moreno Valley |
| 92562, 92563 | Murrieta |
| 92584, 92586 | Menifee |
| 92587 | Canyon Lake |
| 92592 | Rancho California |
| 92595 | Wildomar |
| 92603 | Irvine |
| 92630 | El Toro |
| 92660 | Newport Beach |
| 92673 | San Clemente |
| 92883 | Corona |
| 93012 | Camarillo |
| 93036 | Oxnard |
| 93534, 93536 | Del Sur |
| 93535 | Hi Vista |
| 93551 | City Ranch |