Lease Default Probability Calculator

Score tenant default probability using rent-to-income, credit, tenure, and deposit. Gets to a one-year default probability.

Rent-to-income %

Credit score

Prior tenure months

Deposit coverage months

Default probability

2.65%

Risk band

Low

Recommendation

Standard terms

How the math works

Score combines rent burden, credit, tenure, deposit. Each lever maps to a default-rate lift over base.

Use as rank-ordering tool, not absolute predictor. Your rejection rate trades off with lease-up speed. A/B test threshold changes against 90-day delinquency data.

How to Use

Enter rent-to-income ratio.
Enter credit score.
Enter tenure months.
Enter deposit coverage months.
Read default probability.

Frequently Asked Questions

What drives default?

Rent burden over 40% of income is strongest single driver. Credit score < 600 doubles base rate. Under 6 months tenure = new-tenant risk. Thin deposits remove buffer.

Model limits?

This is a heuristic scoring tool, not underwriting software. Real defaults also involve job loss, medical, family — things you can't measure. Use as relative ranker.

When to reject?

Probability over 10% = reject or require cosigner. 5-10% = require 2-month deposit. Under 5% = standard terms. Tune thresholds to local market.

What documentation matters here?

Written leases, move-in/move-out inspections with photographs, ledger entries showing every payment and charge, served notices with proof of service, and contemporaneous emails or texts. Courts weigh written evidence heavily; informal understandings rarely stand. Institutional operators run a monthly file audit to catch gaps before they matter. Good paper trails recover most of what's owed.