Display screen or portion thereof with a graphical user interface

The patent or application file contains at least one drawing executed in color. Copies of this patent or patent application publication with color drawings will be provided by the Office upon request and payment of the necessary fee.

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

FIG. 2 is a second image thereof; and,

FIG. 3 is a third image thereof.

The broken lines showing a display screen or portion thereof form no part of the claimed design.

The appearance of the image transitions sequentially between the images shown in FIGS. 1 - 3 . The process or period in which an image transitions to another forms no part of the claimed design.