Disclaimer
An educational estimate — not a pre-approval.
keepitrentit.com helps you understand the conventional departing-residence rental offset and how it moves your debt-to-income ratio. It's a starting point for your own planning, not a substitute for a lender's decision or professional guidance.
Not professional advice
The information and estimates on this site are provided for general educational purposes only. They are not lending, financial, tax, legal, or insurance advice, are not a pre-approval or a rate quote, are not a substitute for advice from a qualified professional, and don't create any lending or advisory relationship. Keeping a home, renting it out, and carrying two mortgages is a six-figure decision with real consequences — before you act, confirm your situation with a licensed loan officer.
Estimates, not underwriting decisions
The calculator produces an estimate, not a pre-approval, an eligibility determination, or a guarantee that you'll qualify for any loan. In particular:
- The 75% factor and net-rent-vs-PITIA method. The tool models the mainstream conventional (Fannie/Freddie-style) departing-residence rule: 75% of projected gross rent, netted against the full existing PITIA, with a surplus added to income or a shortfall added to debt. This is the widely-cited method; your lender applies it against the current Selling Guide and its own worksheets.
- The DTI ceiling. The 45–50% back-end ceiling shown is a typical range, not a fixed cap. The real limit is driven by the automated-underwriting decision (Fannie's DU or Freddie's LPA) for your full file and by individual lender overlays.
- Documentation. To count projected rent, lenders generally need supporting documentation, such as a fully executed lease and often an appraiser's rent schedule. A rent number you hope to charge is not the same as rent the file can use.
- Reserves. Separately from DTI, conventional guidelines typically require reserves (months of PITIA, often on each property). This tool deliberately does not compute a reserve figure; budget for it and confirm the requirement with your lender.
Conventional only — other loan types differ
This tool models the mainstream conventional (Fannie/Freddie-style) departing-residence offset only. FHA, VA, USDA, jumbo, and non-QM programs apply different rental-income and occupancy rules and are not modeled here. It also models a departing residence being converted to a rental — not a "second home," which is owner-occupied and cannot use rental income to qualify at all.
Time-sensitive and subject to change
Conventional underwriting guidelines are updated through Selling Guide announcements, and the departing-residence and reserve rules are among the areas that change. This tool reflects the widely-cited conventional method as of its "Last updated" date. Verify the current Fannie Mae Selling Guide (B3-3.8-01, Rental Income) and the Freddie Mac equivalent before relying on any figure.
Verify before you rely on it
For a real decision, take your numbers to a licensed loan officer and confirm the current Selling Guide and your specific automated-underwriting (DU/LPA) findings. We do our best to keep the method accurate and to cite primary sources, but we make no warranty of accuracy or completeness and accept no liability for decisions made based on this site. See our terms of use.
No affiliation
keepitrentit.com is an independent tool operated by Red Goggles LLC. It is not affiliated with, endorsed by, or connected to Fannie Mae, Freddie Mac, any lender, mortgage broker, or financial institution.
Last updated: June 4, 2026