The thermal and chemical expansion coefficients for La0.2Sr0.8Fe0.55Ti0.45O3-x were measured at 800 <= T <= 1200 degrees C and at similar to 1 x 10(-15) <= pO(2)<= 0.21 atm. Measurements of the total expansion coefficient in air, on heating and cooling between room temperature and 1200 degrees C, are reproducible. The average thermal expansion coefficient of La(0.2)Sr(0.8)Fc(0.55)T(i0.45)O(3-x) is 9.3 +/- 1.1 X 10(-6) K-1 over the whole temperature range, similar to the values reported for other titanium substituted perovskites and yttria-stabilized zirconia. The chemical expansion coefficients measured at 800 degrees C vary linearly with the degree of oxygen non-stoichiometry. At higher temperatures, the chemical expansion shows a pronounced non-linear dependence on stoichiometry. At oxygen partial pressures below similar to 10(-6) atm, the expansion shows evidence of the slow kinetic behavior previously observed in stoichiometry and conductivity measurements. (c) 2005 Elsevier B.V. All rights reserved.