Total monthly cost of ownership
Cost to Own a Home in Marietta-Alderwood, Washington
A $493,000 home here costs
$3,539per month, all in — with 20% down at today's 6.66% 30-year fixed rate.
A standard mortgage calculator would have told you $2,535. The real number is $1,004 higher every month — 40% 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.
Marietta-Alderwood against Whatcom County and Washington
| Measure | Marietta-Alderwood | Whatcom County |
|---|---|---|
| Median home value | $493,200 | $536,100 |
| Median property tax | $3,815 | $3,819 |
| Effective tax rate | 0.774% | 0.712% |
| Median gross rent | $1,450 | $1,465 |
| Population | 3,569 | 228,432 |
The weather behind that power bill
Marietta-Alderwood sits in Whatcom County, which averages a high of 77.8°F in its hottest month and a low of 32.1°F in its coldest, with 83" of precipitation a year and 46% of it in a single three-month stretch. That climate drives 126 cooling and 5,664 heating degree days, which is what sets the $134 electricity line above.
See the full climate breakdown for Whatcom County — month by month temperatures, rainy season timing, snowfall and heating and cooling costs.
Other cities in Whatcom County
Full Whatcom County cost breakdown · Every county in Washington
Common questions
How much does it cost to own a home in Marietta-Alderwood?
A $493,000 home in Marietta-Alderwood, Washington costs approximately $3,539 per month with 20% down at 6.66%. That is $2,535 principal and interest, $318 property tax, $73 homeowners insurance, $202 utilities and $411 set aside for maintenance.
What is the property tax rate in Marietta-Alderwood?
Marietta-Alderwood has an effective property tax rate of 0.774%, based on a median home value of $493,200 and median real estate taxes of $3,815. That is higher than the Whatcom County average of 0.712%.
What is the average home price in Marietta-Alderwood?
The median owner-occupied home value in Marietta-Alderwood, Washington is $493,200, against $536,100 across Whatcom County.
Is it cheaper to rent or buy in Marietta-Alderwood?
Median gross rent in Marietta-Alderwood is $1,450 a month, against $3,539 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 Marietta-Alderwood — 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.