FT FinToolSuite

Mortgage Planning

Rental Offset Mortgage Affordability Explained

Rental offset, decoded. You will see what it means, when it can mislead, why conservative rent estimates help, and a simple offset-off vs offset-on example.

Published: January 1, 2026 · Updated: January 1, 2026 · By FinToolSuite Editorial

Open the stress tester

Run offset-off and offset-on scenarios to see how outputs change.

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Disclaimer

  • Educational only. Rental income is uncertain. Examples are illustrative. No guarantees.

Rental offset basics

Rental offset reduces modeled costs using expected rental income. If estimates are high or variable, it can mask risk. Conservative assumptions help.

Two-scenario approach

Create one scenario with offset off. Duplicate and add a conservative offset percent (for example 50%). Compare DTI tails, safe loan, and default probability.

Illustrative example

Offset off: housing costs are fully counted, DTI mid is higher. Offset at 50%: housing cost line drops, DTI mid lowers, but the 90th percentile may still show stress if rent is uncertain.

Try it in the tool

FAQs

Should I use 100% offset?

Consider conservative amounts; full rent is uncertain. This is not advice.

Do I change other inputs?

Keep other assumptions the same when comparing offset on vs off.

Where is privacy info?

See Privacy Policy.

Compare offset settings

Open the mortgage affordability stress tester, run offset-off and offset-on scenarios, and compare outputs.

Open the stress tester