Construction Loan Calculator – Calculate Interest During Building

Calculate short-term interest-only draw payments while building a new custom home with our free Construction Loan Calculator.

Construction Loan Calculator – Calculate Interest During Building
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Estimated Monthly Interest During Build
Total Interest Paid During Construction
Final 30-Year Permanent Mortgage Payment
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History — Construction Loan Calculator – Calculate Interest During Building

# Time Budget Rate % Monthly Interest Total Build Int Permanent Pmt Action

Phasing Breakdown

  1. Building Draw Phase: Funds disbursed in stages to contractors. Monthly payments are interest-only based on the drawn balance.
  2. Permanent Mortgage Phase: Loan converts into a standard 15 or 30-year amortizing mortgage upon certificate of occupancy.

Construction Loan Cost Projections ($450,000 Budget @ 7.5%)

Build Phase (Avg 50% Drawn) Duration Monthly Payment Phase Total Cost
Construction Build Phase 12 Months $1,406.25 / mo (Interest Only) $16,875 (Build Interest)
Permanent Mortgage Phase 30 Years $3,146.42 / mo (P&I) $682,711 (Permanent Interest)

Frequently Asked Questions

How do construction loans work?

Construction loans provide short-term financing where funds are disbursed to builders in draw stages. Borrowers only pay interest on funds drawn during construction.

What is a construction-to-permanent loan (single-close loan)?

A construction-to-permanent loan combines the short-term construction financing and the long-term permanent mortgage into a single loan with one closing, avoiding dual closing costs.