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521 C St, Martinez, CA 94553 Property Records

Contra Costa County property record for 521 C St, Martinez, CA 94553 · Last verified July 2026

Property Summary

Property TypeSingle Family Home
Details4 bd · 2 ba · 1,624 sqft · built 1929
Lot Size0.099 acres (4,320 sqft)
Owner2 Company Names on File
Last Sale$706,000 (Oct 2025)
Tax Bill$8,821 (2025)
Deeds & MortgagesOct 2025 Sale & Mortgage
Aug 2020 Transfer
Flood ZoneZone AO (high risk)
APN372-203-003-2

Property Details

APN / Parcel Number

Primary APN372-203-003-2
Alternative APN
  • 372-203-003

Interior

Bedrooms4 Beds
Full Baths2 Baths
Total Rooms8 Rooms
Stories1 Story
Building Area1,624 sqft Living Area
Gross Area1,000 sqft
1st Floor Area1,000 sqft

Exterior

Year BuiltBuilt 1929
Effective Year BuiltEffective 1936
Lot Area4,320 sqft (0.099 acres)
Garage Area203 sqft
Parking Spaces1 Parking Space

Location & Zoning

Street Address521 C ST
CityMARTINEZ
StateCA
Zip94553-3201
Property CategoryResidential
Property TypeResidential > Single Family > Home
Legal DescriptionSUBN OF BLKS 90 & 91 15
Legal SubdivisionMARTINEZ
Legal Block90,91
Legal Lot Number15
JurisdictionCONTRA COSTA CA
Township / Civil DivisionCENTRAL CONTRA COSTA
Census Block Group3
Census Block3006
Census Tract318000

Owner

Source: Contra Costa County records · APN 372-203-003-2

Assessment roll updated July 14, 2026 · Last verified July 2026

Owner names and exact recorded amounts shown locked on this page are available instantly with a free trial.

Owner of Record2 Company Names on File
Mailing Address521 C ST, MARTINEZ, CA 94553-3201
Owner TypeCompany
VestingLife Tenant

Deeds, Mortgages & Sale History

DateDocument
Oct 22, 2025Grant Deed, Transfer · Conventional Mortgage
STONECASTLE LAND AND HOME FINANCIAL
Aug 06, 2020Quit Claim Deed, Transfer
NOT AVAILABLE

Assessor's Deed Record

Deed Names2 Verified Names on Deed
Last SaleOct 22, 2025 · Amount on Record
Deed SaleOct 22, 2025 · Amount on Record
Prior SaleNov 08, 2013 · Amount on Record
Deed Document Number2025111613
Prior Transfer DateJul 17, 2020
Prior Transfer Doc0000163209
Record UpdatedSep 20, 2026

October 2025: Grant Deed, Transfer

Document TypeGrant Deed
JurisdictionCONTRA COSTA CA
Recording DateOct 22, 2025
Property Address521 C ST, MARTINEZ, CA 94553-3201
Document Number0000111613
Map ReferenceMB 21 PG 567
Instrument DateOct 15, 2025
Instrument2025- 111613
Transaction TypeTransfer
Record UpdatedNov 03, 2025
Title CompanyPLACER TITLE COMPANY

Transaction

AmountAmount Recorded
DownpaymentDownpayment on File
Loan-to-Value (LTV)LTV on Record
Tax$0.00
Amount AccuracyRounded by County
Additional
  • Arm's Length

Transferred From (Grantor/Seller)

NameVerified Name

Transferred To (Grantee/Buyer)

NameVerified Name
Address520 WANO ST, MARTINEZ, CA 94553-3237

Mortgage

Document Number0000111614
DateOct 22, 2025
Instrument2025- 111614
Lender
NameSTONECASTLE LAND AND HOME FINANCIAL
TypeMortgage Company
Agreement
TypeConventional Mortgage
AmountAmount Recorded
Term361 Months
DueNov 07, 2055

August 2020: Quit Claim Deed, Transfer

Document TypeQuit Claim Deed
JurisdictionCONTRA COSTA CA
Recording DateAug 06, 2020
Property Address521 C ST, MARTINEZ, CA 94553-3201
Document Number0000163209
Instrument DateJul 17, 2020
Instrument163209
Transaction TypeTransfer
Record UpdatedAug 24, 2020
Title CompanyNOT AVAILABLE

Transaction

Tax$0.00
Additional
  • Quitclaim
  • Intrafamily Transfer

Transferred From (Grantor/Seller)

NameVerified Name

Transferred To (Grantee/Buyer)

NameVerified Name
RelationshipRevocable Trust
Address6201 HILLSIDE DR EL SOBRANTE CA 948033619, EL SOBRANTE, CA 94803-3619

Tax Assessment & Valuation

Source: Contra Costa County records · Assessment roll updated July 14, 2026 · Last verified July 2026

Property Jurisdictions

TypeName
StateCalifornia
CountyContra Costa County
MunicipalityMartinez City
Unified School DistrictMartinez Unified School District (KG - 12)

Tax Bill & Assessment History

Assessed value is set for property tax purposes and is not a market price estimate.

YearTax BillAssessed Value
2026$706,000 (+10.31%) Land $475,000 Building $231,000
2025$8,821.00 (+46.26%)$640,000 (+53.66%) Land $455,000 Building $185,000
2023$6,031.00 (-3.6%)$416,507 Land $225,516 Building $190,991
2022$6,256.00

Flood & Wildfire

Source: FEMA National Flood Hazard Layer, Contra Costa County (06013C), updated October 12, 2026 · FEMA OpenFEMA NFIP redacted claims and policies, census block group 060133180003, refreshed September 2026 · USDA Forest Service Wildfire Risk to Communities, 2nd edition (2024), fuels as of 2020 · Last verified October 2026

Flood

FEMA Flood ZoneZone AO
sheet flow 1–3 ft
Special Flood Hazard AreaYes
Flood HazardHigh
100-Year FloodplainYes
1% annual chance
FloodwayNo
Base Flood ElevationVaries along the reach; see FIRM
Flood Insurance RequirementRequired (federally backed mortgages)
Flood Insurance CostPremium on Record
median of 109 individual NFIP policies nearby
Nearby Flood Policies109 in force
82 of 109 on primary residences
Nearby Flood Claims32 (1980–2019)
Claims Outside the SFHA3 of 32
Most Recent ClaimFeb 2019
Flood Events
  • Severe Storms, Flooding, Mudslides, And Landslides (Jan 2006), 12 claims
  • Severe Storms, Flooding, Mud And Landslides (Jan 1997), 5 claims
  • Severe Storms, Flood, Mudslides & High Tide (Jan 1982), 6 claims

Wildfire

Wildfire RiskModerate
above 60% of the US · above 36% of California
Wildfire LikelihoodAbout 1 in 610 per year
ExposureIndirect
within ember reach

Values are read at the parcel center point; flood claims are located to the census block group, not this parcel; lenders make the official flood determination.

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