Originating & Underwriting

New Desktop Underwriter User Interface

Now available to all lenders and sponsored mortgage brokers
Need help submitting the redesigned Form 1003 and DU MISMO v3.4 file? 

Look for your answers here first. 

Read the Quick Guide  New DU UI job aids   DU Error Codes


The redesigned Desktop Underwriter® (DU®)/Desktop Originator®(DO®) user interfaces (UIs) feature an updated look and feel and support the redesigned Uniform Residential Loan Application (URLA) (Fannie Mae Form 1003). Starting Jan. 1, 2021, all Fannie Mae customers and sponsored mortgage brokers can start to submit casefiles to DU/DO through the new UIs. 

The new UIs will only accept and access submissions of loans in the new DU Specification MISMO V. 3.4 (DU Spec). Any loans in the 1003 3.2 or MISMO V. 2.3.1 formats should be accessed and submitted in the classic version of DU/DO (accessible on the DU webpage).

All new loans dated on or after March 1, 2021, must be submitted using the redesigned URLA through the new UIs. Users may continue to use the classic DU/DO UIs for existing casefiles dated prior to March 1, 2021, until they are retired on March 1, 2022.

Questions & Feedback

To provide feedback on the new interface, please call 800-2FANNIE (800-232-6643), choose Option 1, and then Option 1 again.