We have conducted measurements of the linear electro‐optic coefficient (r41) and electrogyratory coefficient (&eegr;41) in Bi12TiO20at 633 nm. A precise knowledge of these coefficients is important for evaluating the holographic recording properties of this photorefractive material. We have employed both transverse and longitudinal electric field geometries. For each geometry, we present the results of dc as well as ac techniques. Based on these results we findr41=5.75±0.10 pm/V and ‖&eegr;41‖≤0.30±0.05 pm/V. We critically examine our measurements and discuss their relative accuracy. Our findings are compared to those previously reported by other investigators.