Improved two-bit transform-based motion estimation algorithms are proposed in this paper. By extending the typical two-bit transform (2BT) matching criterion, the proposed algorithms enhance the motion estimation accuracy with almost the same computational complexity, while preserving the binary matching characteristic. Experimental results show that the proposed algorithm achieves peak-to-peak signal-to-noise ratio (PSNR) gains up to 0.42 dB compared with the conventional 2BT-based motion estimation.