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.

FIG. 1 is a first front view of a display screen or portion thereof with a transitional graphical user interface showing a first image;

FIG. 2 is a second front view of a display screen or portion thereof with a transitional graphical user interface showing a second image; and,

FIG. 3 is a third front view of a display screen or portion thereof with a transitional graphical user interface showing a third image.

The appearance of the display screen or portion thereof with a transitional graphical user interface sequentially transitions between the images shown in FIGS. 1 - 3 . The process or period in which one image transitions to another image forms no part of the claimed design.

The dashed broken lines depict portions of the display screen or portion thereof with a graphical user interface that form no part of the claimed design. The dot-dashed broken lines depict the display screen or portion thereof and form no part of the claimed design. Tonal shading indicates a contrast in appearance forming part of the claimed design.