A third flag was adopted in October 1975, shortly after Spokane hosted the World's Fair and was named an All-America City; its design included a simple black ring and two bands of chartreuse green and aqua blue running diagonally across a white field.

[9] A new city flag was proposed in 1958 by local businessman S. Luther Essick, who also served as president of the Spokane chamber of commerce and the Lilac Festival Association.

[19] The second city flag consisted of a lilac purple field with four white lines extending from the corners towards the center, where several images were displayed.

The center's design included the city skyline, the Monroe Street Bridge above Spokane Falls, and a spray of lilac blossoms.

[21] The city adopted a new flag on October 6, 1975,[22] which was designed by art director Lloyd L. Carlson of a local advertising company that had previously worked on the Expo '74 logo.

[16][23] The first flag to be produced with the new design was completed in March 1976 by two members of the St. John's Episcopal Church and presented two months later to a delegation from Nishinomiya, Spokane's sister city in Japan.

[24][25] A second flag was made by members of the Spokane Falls Needlework Guild over a two-month period before an annual stitchery convention in March 1977.

[25] The 1975 flag consisted of a white field with diagonal bands of chartreuse green and aqua blue that run from the hoist to bottom center.

[16] The center ring is joined by a golden sun in the top right corner, and the text "City of Spokane" is to the bottom right in all capital letters.

The contest allowed for three submissions per person and required a simple design meeting basic criteria set by vexillologists on the flag commission.