Contra Costa County property record for 4321 Calsite Ct, Antioch, CA 94509
| Property Type | Single Family Home |
|---|---|
| Details | 3 bd · 2.5 ba · 2,454 sqft · built 1997 |
| Lot Size | 0.184 acres (8,000 sqft) |
| Owner | Individual Name on File |
| Last Sale | $397,500 (Apr 2003) |
| Tax Bill | $6,823 (2025) |
| Deeds & Mortgages | Dec 2025 Transfer |
| Flood Zone | Zone X (minimal risk) |
| APN | 053-520-029-9 |
| Primary APN | 053-520-029-9 |
|---|---|
| Alternative APN |
|
| Bedrooms | 3 Beds |
|---|---|
| Full Baths | 2.5 Baths |
| Half Baths | 1 Half Bath |
| Total Rooms | 8 Rooms |
| Stories | 2 Stories |
| Building Area | 2,454 sqft Living Area |
| 1st Floor Area | 1,209 sqft |
| 2nd Floor Area | 1,245 sqft |
| Year Built | Built 1997 |
|---|---|
| Effective Year Built | Effective 1997 |
| Lot Area | 8,000 sqft (0.184 acres) |
| Garage Type | Attached |
| Garage Area | 599 sqft |
| Parking Spaces | 2 Parking Spaces |
| Street Address | 4321 CALSITE CT |
|---|---|
| City | ANTIOCH |
| State | CA |
| Zip | 94509-8942 |
| Property Category | Residential |
| Property Type | Residential > Single Family > Home |
| Legal Description | T7999 L131 |
| Legal Subdivision | 7999 HO 3 DAY BREAK |
| Legal Tract | 7999 |
| Legal Lot Number | 131 |
| Jurisdiction | CONTRA COSTA CA |
| Township / Civil Division | ANTIOCH-PITTSBURG |
| Census Block Group | 3 |
| Census Block | 3010 |
| Census Tract | 355109 |
4321 Calsite Ct is owned and occupied by an individual who acquired it in December 2025.
Source: Contra Costa County records, as of July 14, 2026
| Owner of Record | Individual Name on File |
|---|---|
| Mailing Address | 4321 CALSITE CT, ANTIOCH, CA 94509-8942 |
| Occupancy | Owner Occupied |
| Owner Type | Individual |
| Vesting | Sole Owner |
Owner names and exact recorded amounts are on file and can be viewed instantly on this page with a free 10-day trial.
| Deed Names | Name on Deed |
|---|---|
| Last Sale | Apr 24, 2003 · Amount on File |
| Deed Sale | Apr 24, 2003 · Amount on File |
| Prior Sale | Aug 21, 2001 · Amount on File |
| Deed Document Number | 2003187625 |
| Last Transfer Date | Dec 12, 2025 |
| Transfer Doc | 0000143960 |
| Record Updated | Oct 29, 2026 |
| Document Type | Intrafamily Transfer |
|---|---|
| Jurisdiction | CONTRA COSTA CA |
| Recording Date | Dec 26, 2025 |
| Property Address | 4321 CALSITE CT, ANTIOCH, CA 94509-8942 |
| Document Number | 0000143960 |
| Map Reference | MB 388 PG 1 |
| Instrument Date | Dec 12, 2025 |
| Instrument | 2025- 143960 |
| Transaction Type | Transfer |
| Record Updated | Jan 7, 2026 |
| Tax | $0.00 |
|---|---|
| Amount Accuracy | No Consideration Stated |
| Additional |
|
| Name | Verified Name |
|---|
| Name | Verified Name |
|---|---|
| Relationship | Separate Estate/Property |
| Address | 4321 CALSITE CT, ANTIOCH, CA 94509-8942 |
The 2025 property tax bill for 4321 Calsite Ct was $6,823.
Source: Contra Costa County assessment roll, as of July 14, 2026
| Type | Name |
|---|---|
| State | California |
| County | Contra Costa County |
| Municipality | Antioch City |
| Unified School District | Antioch Unified School District (KG - 12) |
| Year | Tax Bill | Assessed Value |
|---|---|---|
| 2026 | $599,760 (+2%) Land $155,104 Building $444,656 | |
| 2025 | $6,823.00 | $588,001 Land $152,063 Building $435,938 |
| 2023 | $6,431.00 (+1.61%) | $565,170 Land $146,159 Building $419,011 |
| 2022 | $6,329.00 |
Assessed value is set for property tax purposes and is not a market price estimate.
FEMA maps place 4321 Calsite Ct in Zone X, an area of minimal flood risk.
Source: FEMA National Flood Hazard Layer, effective October 12, 2026
| FEMA Flood Zone | Zone X minimal risk |
|---|---|
| Flood Insurance Requirement | Not required lenders may require it |
Values are read at the parcel center point; lenders make the official flood determination.
The area around 4321 Calsite Ct has no burnable land within ember reach, so its wildfire risk is not rated.
Source: USDA Forest Service Wildfire Risk to Communities (2nd edition), as of 2024
| Wildfire Risk | Not rated no burnable land within ember reach |
|---|
Values cover an area roughly 900 ft across, not the parcel itself; insurers use their own ratings.
Source: EPA Safe Drinking Water Information System, as of September 2026
| Water System | CITY OF ANTIOCH serves 116,781 people · EPA ID CA0710001 |
|---|---|
| Water Source | Surface water |
| Last State Inspection | Jan 2024 |
| Lead | Under 1 ppb (2022–2024) action level 15 ppb |
| Water Quality | None last 10 years |
|---|---|
| Treatment and Procedure | None last 10 years |
| Monitoring and Reporting | None last 3 years |
Results are for the whole water system, not water tested at this address; lead at the tap also depends on the building's own pipes.
Source: FCC Broadband Data Collection, based on 606 locations within half a mile, as of December 31, 2025
| Provider | Max Down / Up (Mbps) |
|---|---|
| Xfinity Cable | 2,000 / 250 |
| Unwired Fixed Wireless | 300 / 25 |
| AT&T DSL · Fiber, Fixed Wireless in parts of the area | 100 / 20 |
May also be available: Verizon.
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