Display Screen or Portion Thereof with a Graphical User Interface

A portion of the disclosure of this patent document contains material to which a claim for copyright is made. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure, as it appears in the Patent and Trademark Office patent file or records, but reserves all other copyright rights whatsoever.

The FIGURE is a front view of a display screen or portion thereof with a graphical user interface.

The dot-dashed broken lines represent boundaries of the claimed design and the display screen or portion thereof and form no part of the claimed design. The dashed broken lines depict portions of the display screen or a portion thereof with a graphical user interface that form no part of the claimed design. The broken lines showing text and numbers form no part of the claimed design.