Mortgage Planning
Joint Income vs Single Income Mortgage Stress Test
Joint vs single income, made simple. See how combining incomes changes DTI and the safe loan, and how a one-income buffer looks with two quick examples you can rerun in the tool.
Published: January 1, 2026 · Updated: January 1, 2026 · By FinToolSuite Editorial
Open the stress tester
Run combined and single-income scenarios to see how outputs change.
Disclaimer
- Educational only. No guarantees. Examples are illustrative.
Joint vs single income basics
Combining incomes can lower DTI, while relying on one income can show a buffer. Testing both highlights sensitivity to income changes.
Example scenarios
Example 1: Combined income $12,000/month with current costs. DTI mid is lower, safe loan may be higher.
Example 2: Single income $8,000/month with the same costs. DTI mid and tails rise; recommended safe loan may drop.
Metrics to watch
- DTI mid and high percentiles.
- Recommended safe loan.
- Default probability direction.
FAQs
Should I change debts?
Keep debts the same when comparing income setups to isolate the income effect.
How do I label scenarios?
Use clear labels like “Joint income” and “Single income” with dates.
Where is privacy info?
See Privacy Policy.
Compare income setups
Open the mortgage affordability stress tester, run combined and single-income scenarios, and compare outputs side by side.