Beyond the Guide: A Deep Dive into Mortgage Underwriting - Rental Income After the Rewrite

Fannie Mae has moved rental income into its own Selling Guide section, B3-3.8, with the latest revisions applying to applications dated on or after November 1, 2026. This post walks through the gates for using rental income, the documentation path for each property type, the 75 percent calculation, and the defects QC reviews find most often.