Deep‐level defects in as‐grown, ingot‐annealed, and wafer‐annealed samples of semi‐insulating gallium arsenide have been investigated by spatially resolved measurements of room‐temperature photoluminescence, infrared absorption, free‐carrier lifetime, and resistivity. High‐temperature ingot annealing mainly causes a homogenization of the EL2 distribution. Rapid cooling from a wafer annealing process atT>900 °C suppresses the formation of the previously lifetime‐limiting recombination center. After wafer annealing the EL2 defect may be the dominant recombination center, while in as‐grown and ingot‐annealed material lifetime is limited by a different trap. There is experimental evidence that this trap is related to the 0.8‐eV luminescence band and that its density is spatially anticorrelated to the EL2 distribution. Based on lifetime measurements and a correlation of EL2 and photoluminescence topographs, we developed a recombination model, which explains the relationship between defect densities, and photoluminescence. The effect of surface recombination is described by a numerical calculation.