Display Screen or Portion Thereof with Transitional 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 drawing(s) will be provided by the Office upon request and payment of the necessary fee.

FIG. 1 is a front view of a first image in a sequence of a first embodiment of a display screen or portion thereof with transitional graphical user interface according to the claimed design; and

FIG. 2 is a front view of a second image thereof;

FIG. 3 is a front view of a first image in a sequence of a second embodiment of a display screen or portion thereof with transitional graphical user interface according to the claimed design; and,

FIG. 4 is a front view of a second image thereof.

The appearance of the transition is sequential from FIG. 1 to FIG. 2 in the first embodiment, and from FIG. 3 to FIG. 4 in the second embodiment. The process or period in which an image transitions to another image forms no part of the claimed design.

The shading depicts a contrast in appearance.

The longer-dash broken lines illustrate an electronic device. The e intermediate-length broken lines illustrate the perimeter of a display screen. The remaining broken lines illustrate features within the graphical user interface. The broken lines form no part of the claimed design.