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 innermost dot-dashed broken lines depict the display screen or portion thereof. All dot-dashed broken lines outside the display screen depict the environment of an electronic device. The dashed broken lines depict portions of the graphical user interface. All broken lines form no part of the claimed design.