Buyer tool
Mortgage Calculator
Enter your numbers and see the full monthly payment — principal, interest, property taxes, homeowners insurance, HOA, and PMI. Defaults are tuned for King County. Adjust anything.
Estimate only. Actual payment depends on lender pricing, points, taxes assessed by your county, escrow setup, and PMI tier. Loan officers we trust can quote real rates and APRs — ask us for a referral.
How this calculator works
The principal and interest portion uses the standard amortization formula M = P · r(1+r)n / ((1+r)n − 1), where P is the loan amount, r is the monthly rate (annual ÷ 12), and n is the number of payments (years × 12).
Property tax is calculated as a flat percentage of the home price divided by 12 — close enough for King, Snohomish, and Pierce County effective rates. Insurance and HOA are passed through directly. PMI is applied only when your down payment is below 20% and uses your annual rate against the loan balance.
Seattle-specific notes
- Property tax in King County is roughly 0.93–1.05% effective; Bellevue and Mercer Island sit on the lower end, while parts of Seattle proper run higher with voter-approved levies.
- Jumbo loans kick in above the conforming limit (currently around $1.0M in King/Snohomish/Pierce). Jumbo rates are often comparable to conforming, but down-payment requirements differ.
- Earnest money in WA is typically 1–3% of the offer price. It's not part of monthly cost, but plan for it on top of your down payment.
Want this checked against real numbers?
If you're house-hunting in Greater Seattle, we'll walk through your real lender quote, the seller-offered buyer-agent commission, and the rebate you'd get with our capped buyer fees. Get in touch →