Total monthly cost of ownership
Cost to Own a Home in Castle Rock, Washington
A $301,000 home here costs
$2,242per month, all in — with 20% down at today's 6.66% 30-year fixed rate.
A standard mortgage calculator would have told you $1,547. The real number is $694 higher every month — 45% more than the payment most buyers budget for.
Where every dollar goes
Only the first line is a mortgage payment. Change any assumption above and every figure below recalculates.
Castle Rock against Cowlitz County and Washington
| Measure | Castle Rock | Cowlitz County |
|---|---|---|
| Median home value | $301,000 | $367,400 |
| Median property tax | $2,356 | $2,988 |
| Effective tax rate | 0.783% | 0.813% |
| Median gross rent | $1,326 | $1,169 |
| Population | 2,298 | 111,539 |
The weather behind that power bill
Castle Rock sits in Cowlitz County, which averages a high of 82.3°F in its hottest month and a low of 37.2°F in its coldest, with 40.66" of precipitation a year and 42% of it in a single three-month stretch. That climate drives 427 cooling and 4,155 heating degree days, which is what sets the $134 electricity line above.
See the full climate breakdown for Cowlitz County — month by month temperatures, rainy season timing, snowfall and heating and cooling costs.
Other cities in Cowlitz County
Full Cowlitz County cost breakdown · Every county in Washington
Common questions
How much does it cost to own a home in Castle Rock?
A $301,000 home in Castle Rock, Washington costs approximately $2,242 per month with 20% down at 6.66%. That is $1,547 principal and interest, $196 property tax, $45 homeowners insurance, $202 utilities and $251 set aside for maintenance.
What is the property tax rate in Castle Rock?
Castle Rock has an effective property tax rate of 0.783%, based on a median home value of $301,000 and median real estate taxes of $2,356. That is lower than the Cowlitz County average of 0.813%.
What is the average home price in Castle Rock?
The median owner-occupied home value in Castle Rock, Washington is $301,000, against $367,400 across Cowlitz County.
Is it cheaper to rent or buy in Castle Rock?
Median gross rent in Castle Rock is $1,326 a month, against $2,242 to own the median home all in. Renting costs less month to month here, though renting builds no equity.
Sources & methodology
- Median home value, real estate taxes, gross rent and population for Castle Rock — US Census Bureau, American Community Survey ACS 2023 5-Year, place-level tables.
- Homeowners insurance — NAIC average premium for Washington.
- Electricity price — EIA Electric Power Monthly Table 5.6.A.
- Mortgage rate — Freddie Mac PMMS, refreshed weekly.
- Maintenance (1%/yr) and water and sewer ($68/mo) are national estimates. Every assumption above is editable.