Castro Valley vs Cordelia, Fairfield
Castro Valley carries an effective property tax rate of 1.20% of assessed value and Cordelia, Fairfield carries 1.18%, both for fiscal year 2025-26. On one identical reference loan the monthly carrying costs are $9,893 and $9,864 — $29 apart, with Cordelia, Fairfield lower. To Oakland City Center at AM peak the fastest published commutes are 28 min by BART from Castro Valley and 60 min by car from Cordelia, Fairfield. Every figure is an objective public metric or arithmetic on one, and names its source.
Castro Valley (Alameda County) · Cordelia, Fairfield (Solano County)
| Metric | Castro Valley | Cordelia, Fairfield | Difference |
|---|---|---|---|
| Median $/sqft (SFR) | $650 | $380 | +$270 |
| Effective tax rate | 1.20% | 1.18% | +0.022% |
| Monthly cost, reference loan | $9,893 | $9,864 | +$29 |
| FiDi SF (Montgomery St BART) — BART | 45 min | 85 min | −40 min |
| FiDi SF (Montgomery St BART) — Drive | 50 min | 75 min | −25 min |
| Oakland City Center (12th St BART) — BART | 28 min | 70 min | −42 min |
| Oakland City Center (12th St BART) — Drive | 28 min | 60 min | −32 min |
| Sunnyvale / Mountain View (Sunnyvale Caltrain) — Drive | 50 min | 95 min | −45 min |
Difference is Castro Valley minus Cordelia, Fairfield. Sources are cited on each submarket page.
Castro Valley carries $270 more per square foot than Fairfield (Cordelia) — 71% — and that single spread decides most searches that start with both names on the list. The tax rates land 1.20% in Castro Valley against 1.18% in Fairfield (Cordelia), close enough that price per foot, not the levy, is what moves the payment.
What the same money buys
$1.4M in Castro Valley is a 2,400-2,800 sq ft four-bedroom in Palomares Hills or Five Canyons, 1990s, with a view. The Cordelia sweet spot is $700K-$900K for 2,200-2,800 sq ft built 1995-2010. The median foot costs $650 in Castro Valley against $380 in Fairfield (Cordelia); on a 2,000 sq ft house that is $540,000 of purchase price.
The monthly, matched
Holding the loan constant — $1,600,000, 20% down, 6.5% on a 30-year fixed, $2,400 of insurance, no HOA — Castro Valley totals $9,893 a month at 1.20% and Fairfield (Cordelia) $9,864 at 1.18% — tax lines of $1,603 and $1,573. No Mello-Roos in the older Castro Valley stock. The 1990s Green Valley core in Cordelia largely carries no Mello-Roos.
Commute, measured
To Sunnyvale / Mountain View (Sunnyvale Caltrain): 50 minutes by driving from Castro Valley, 95 by driving from Fairfield (Cordelia) — a 45-minute edge to Castro Valley, or 7.5 hours across a ten-trip week. To Oakland City Center (12th St BART): 28 minutes by BART from Castro Valley, 60 by driving from Fairfield (Cordelia) — a 32-minute edge to Castro Valley, or 5.3 hours across a ten-trip week. I-580 puts Castro Valley 35 minutes from the Bay Bridge at 6 a.m., 60-70 at 8. Cordelia to the Bay Bridge is 50 minutes at 5:30 a.m. and 75-100 minutes at 7:30.
Hazard and insurance
The canyons and hills east of Crow Canyon and Palomares Road are mapped High fire hazard. Green Valley and the hills west of I-680 are mapped High fire hazard. None of this substitutes for the parcel: check CAL FIRE zoning, the FEMA flood panel and CGS seismic hazard mapping, then price the policy in writing.
Choosing between them
Castro Valley answers a need for access to both the I-580 and I-880 corridors. Cordelia fits a 3,000-plus square foot requirement with a three-car garage.
Sources. Rate and payment figures: Alameda County Tax Rates by TRA FY 2025-26; Solano County Tax Rate Book FY 2025-26; City of Fairfield CFD reports, as composited in build/assets/metrics.json — unverified at tax-rate-area level, so read the bill. Minutes shown are AM-peak and door to door, from data/commute/static.csv. Median price per foot is a trailing figure, not a valuation, and the local detail comes from the broker's own transactions.
Compare any two submarkets
| Metric | Castro Valley | Cordelia, Fairfield |
|---|---|---|
| Median $/sqft (SFR) | $650 | $380 |
| Effective tax rate | 1.20% | 1.18% |
| Monthly cost, reference loan | $9,893 | $9,864 |
| Fastest to FiDi SF (Montgomery St BART) | 45 min | 75 min |
| Fastest to Oakland City Center (12th St BART) | 28 min | 60 min |
| Fastest to Sunnyvale / Mountain View (Sunnyvale Caltrain) | 50 min | 95 min |
Same reference loan on both sides; the tax line is the only variable. Commute figures are door-to-door AM-peak estimates. Sources are listed on each submarket page.
Castro Valley detail
| Component | Rate of assessed value |
|---|---|
| Prop 13 general levy | 1.000% |
| County / city voter-approved bonds | 0.042% |
| School district measures | 0.160% |
| Effective rate | 1.20% |
| Mello-Roos / CFD | None recorded |
Source: Alameda County Tax Rates by TRA FY 2025-26 (Alameda County), composited in
build/assets/metrics.json.
Tax Rate Area not yet verified parcel-by-parcel — confirm the rate on the parcel’s own tax bill.
Cordelia, Fairfield detail
| Component | Rate of assessed value |
|---|---|
| Prop 13 general levy | 1.000% |
| County / city voter-approved bonds | 0.010% |
| School district measures | 0.090% |
| Mello-Roos / CFD assessment | 0.080% |
| Effective rate | 1.18% |
| Mello-Roos / CFD | Yes |
Source: Solano County Tax Rate Book FY 2025-26; City of Fairfield CFD reports (Solano County), composited in
build/assets/metrics.json.
Tax Rate Area not yet verified parcel-by-parcel — confirm the rate on the parcel’s own tax bill.
Castro Valley vs Cordelia, Fairfield: questions and answers
- Which has the lower effective property tax rate, Castro Valley or Cordelia, Fairfield?
- Cordelia, Fairfield, at 1.18% of assessed value against 1.20% for fiscal year 2025-26 — a gap of 0.020%. Rates are composited from county tax rate books; each parcel bill governs.
- How much do monthly carrying costs differ between Castro Valley and Cordelia, Fairfield?
- $29 per month on the identical reference loan: Castro Valley $9,893, Cordelia, Fairfield $9,864. Cordelia, Fairfield is lower. Principal and interest are held constant, so the difference is the tax line. Arithmetic only.
- Which has the shorter commute to Oakland City Center, Castro Valley or Cordelia, Fairfield?
- Castro Valley. Castro Valley is 28 min by BART; Cordelia, Fairfield is 60 min by car. Door-to-door, AM peak. Source: data/commute/static.csv.
- What is the price per square foot difference between Castro Valley and Cordelia, Fairfield?
- $270 per square foot: Castro Valley $650, Cordelia, Fairfield $380. Single-family medians, trailing twelve months. A median is not a valuation of any specific property.