Allan H. MacDonald (born December 1, 1951) is a theoretical condensed matter physicist and the Sid W. Richardson Foundation Regents Chair Professor of Physics at The University of Texas at Austin.

He has contributed to theories of the integer and fractional quantum Hall effects, spintronics in metals and semiconductors, topological Bloch bands and momentum-space Berry curvature phenomena, correlated electron-hole fluids and exciton and polariton condensates, and two-dimensional materials.

[10] Pablo Jarillo-Herrero, an experimentalist at Massachusetts Institute of Technology, found that the magic angle resulted in the unusual electrical properties the UT Austin scientists had predicted.

MacDonald received the Canadian Association of Physicists's Herzberg Medal in 1987,[2] the Oliver E. Buckley Prize of the American Physical Society in 2007 with James P. Eisenstein and Steven Girvin,[6] the Ernst Mach Honorary Medal of the Czech Academy of Sciences in 2012,[13] and the Wolf Prize in Physics in 2020 with Bistritzer and Jarrillo-Herrero.

Allan and Susan maintain a seasonal residence in Jimtown overlooking St. George's Bay - the backdrop of their summer days from youth to old age.