21403 Alta Way is a 660 square foot house on a 10,795 square foot lot with 2 bedrooms. Based on Redfin's Monte Rio data, we estimate the home's value is $464,953.
Single-familyProperty Type
1900Year Built
10,795 sq ftLot Size
$704Est. Price/Sq.Ft.
Source:Public Records
Redfin Estimate
$464,953
$176K since August
Recently sold homes
Estimate history
Homes for sale
This home's estimate is 9.6% lower than the average sale price ($515K) of 6 comparable homes.
As the MLS and public records start to fill up, we'll list the details here.
Year
Property tax
Land + Additions
Assessment*
2025
$2,319 (+2.8%)
$61,290 + $91,935
$153,225
2024
$2,255 (+1.7%)
$60,089 + $90,133
$150,222
2023
$2,217 (+2.0%)
$58,911 + $88,366
$147,277
2022
$2,174 (+1.1%)
$57,756 + $86,634
$144,390
2021
$2,150 (−2.2%)
$56,624 + $84,936
$141,560
2020
$2,198 (+4.4%)
$55,514 + $83,271
$138,785
2019
$2,106 (+14.6%)
$54,945 + $82,418
$137,363
2018
$1,838 (+3.8%)
$53,868 + $80,802
$134,670
2017
$1,770 (+247.1%)
$51,777 + $77,665
$129,442
2015
$510 (+0.4%)
$50,762 + $76,143
$126,905
2014
$508 (+0.2%)
$2,590 + $5,594
$8,184
2013
$507 (+5.1%)
$2,590 + $5,594
$8,184
2012
$483 (+0.5%)
$2,579 + $5,569
$8,148
2011
$481 (+0.2%)
$2,529 + $5,460
$7,989
2010
$480
$2,480 + $5,353
$7,833
2009
$480 (−9.0%)
$2,462 + $5,313
$7,775
2007
$528
$2,420 + $5,222
$7,642
Tax history for 21403 Alta Way
Year
Property tax
Land + Additions
Assessment*
2025
$2,319 (+2.8%)
$61,290 + $91,935
$153,225
2024
$2,255 (+1.7%)
$60,089 + $90,133
$150,222
2023
$2,217 (+2.0%)
$58,911 + $88,366
$147,277
2022
$2,174 (+1.1%)
$57,756 + $86,634
$144,390
2021
$2,150 (−2.2%)
$56,624 + $84,936
$141,560
2020
$2,198 (+4.4%)
$55,514 + $83,271
$138,785
2019
$2,106 (+14.6%)
$54,945 + $82,418
$137,363
2018
$1,838 (+3.8%)
$53,868 + $80,802
$134,670
2017
$1,770 (+247.1%)
$51,777 + $77,665
$129,442
2015
$510 (+0.4%)
$50,762 + $76,143
$126,905
2014
$508 (+0.2%)
$2,590 + $5,594
$8,184
2013
$507 (+5.1%)
$2,590 + $5,594
$8,184
2012
$483 (+0.5%)
$2,579 + $5,569
$8,148
2011
$481 (+0.2%)
$2,529 + $5,460
$7,989
2010
$480
$2,480 + $5,353
$7,833
2009
$480 (−9.0%)
$2,462 + $5,313
$7,775
2007
$528
$2,420 + $5,222
$7,642
*Taxable value of land and structures on it ("additions") is determined regularly by local assessors and does not affect market price.
Permits
Nov 12, 2019 • Final
Building permit no plan check
Bathroom
Electrical
Kitchen
Plumbing
Jul 10, 2018 • Final
Building permit no plan check
Upgrade the electrical service.
Electrical
Permit history is from public records and may be incomplete or inaccurate. Redfin and its agents make no representations about the property condition or permit status. Buyers should independently verify all information.
Property details
Interior
Fireplace Information
# of Fireplaces: 1
Has Fireplace
Room Information
# of Rooms: 4
Exterior
Exterior Information
Building Style Type: Square Design
Construction Type: Wood/Steel
Building Construction Quality: Fair
Property Information
Subdivision Name: MONTE RIO PARK TIER G
Living Sq. Ft: 660
Ground Floor Sq. Ft: 576
Building Sq. Ft: 675
# of Stories: 1
Lot Information
# of Buildings: 1
Land Sq. Ft: 10,795
Legal Lot Number: 24,25
Acres: 0.2478
Zoning Code: RR1
County Use Description: SINGLE FAM DWELLING
Financial
Assessor Information
Assessment Year: 2026
Public facts
Beds: 2
Baths: —
Sq. Ft.: 660
Stories: 1.0
Lot Size: 10,795 square feet
Style: Single Family Residential
Year Built: 1900
Year Renovated: 1965
County: Sonoma County
APN: 095135014000
Home facts updated by county records on Aug 13, 2026
Around this home
Schools
Monte Rio Elementary School
Public K-8 • Assigned • 0.7mi
7/10
Analy High School
Public 9-12 • Assigned • 10.7mi
8/10
Provided by GreatSchools
Lifestyle
Provided by Walk Score and Local Logic
Climate risks
1/10 Flood Factor
Minimal risk of a flood reaching the building in the next 30 years
2/10 Fire Factor
0.00% chance of being in a wildfire in next 30 years
2/10 Heat Factor
9 days above 86° expected this year, 24 days in 30 years
1/10 Wind Factor
Minimal risk of severe winds over next 30 years
9/10 Air Factor
17 unhealthy days expected this year, 19 days in 30 years
Provided by First Street
Historical weather
Monte Rio, CA • 95462
Average low and high temperatures (°F)
59
40
60
43
69
44
66
46
74
49
75
51
73
52
82
53
78
53
75
49
62
45
58
44
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Sun exposure
In this area, properties receive around 10.6 hours in
June and 4.9 hours in December, placing it above the
U.S. average for solar exposure.
10.6 hrs
4.9 hrs
JuneDecember
Provided by Shadowmap
Estimated sale price
$442,000 – $535,000
Reach more buyers when you sell with Redfin. Save up to $4,650 in fees.3 minutes to get started.