See what you'll actually pay each month
True Monthly Cost Calculator
Calculate your real monthly housing cost — mortgage, property tax, insurance, HOA, PMI, and maintenance. Uses 2025-2026 Washington State data for realistic defaults.
TL;DR
Pre-approval tells you what a lender will lend. This calculator shows what you will actually pay each month — including tax, insurance, HOA, and maintenance — so you can compare properties on real carrying cost.
What this includes
- Principal and interest
- Property tax (pre-filled with 2025–2026 Greater Seattle defaults by area)
- Homeowners insurance
- HOA dues
- PMI for down payments under 20%
- Monthly maintenance reserve
What buyers often miss
- HOA dues can create a $400–700/month difference between two homes at the same price.
- King County and Snohomish County property taxes should be verified against the actual parcel — assessed value often differs from purchase price.
- Older homes need a realistic maintenance reserve, not zero.
- New construction estimates may shift once the assessor re-evaluates post-purchase.
Greater Seattle notes
- Property tax rates vary: Seattle ~0.99%, Bellevue/Redmond ~0.74%, Kirkland ~0.85%, Snohomish County ~0.79%.
- Condo HOA financial health matters as much as monthly dues — a low-dues HOA with a depleted reserve can face special assessments.
- Verify the actual tax bill for the specific parcel before relying on area defaults.
Enter a purchase price above to see your monthly cost breakdown.
Common questions
Is my pre-approval amount my real budget?▾
Pre-approval tells you what a lender will lend. This calculator shows what ownership actually costs each month — including property tax, insurance, HOA, and a maintenance buffer. Many buyers find the gap between pre-approval and comfortable monthly payment is larger than expected.
Why can two homes at the same price cost different amounts monthly?▾
Property type, HOA dues, property tax rate by city, and maintenance assumptions all vary. Two $1.2M homes in different parts of Greater Seattle can differ by $400–700/month in real carrying cost.
How should I think about the maintenance reserve?▾
A common rule of thumb is 1% of home value per year. For a $900K home, that is $750/month. Many buyers start lower — but older homes, homes with known deferred maintenance, or large lots with wood siding need a higher assumption.
Want a sanity check on a specific listing?
Send the listing and your calculator result to Vera.
Vera Huang is a Washington licensed broker with WeLakeside. She built SeattleHomeWay for analytical Greater Seattle buyers who want to understand the numbers, risks, and tradeoffs before making an offer.