A method of decoding video data includes receiving encoded data for a current block and decoding N bins for a low-frequency non-separable transform (LFNST) index from the encoded data. The N bins comprises a first bin and a second bin. Decoding the N bins comprises context decoding each bin of the N bins. The method further includes determining the LFNST index using the N bins and decoding the encoded data to generate transform coefficients. The method further includes applying an inverse LFNST to the transform coefficients using the LFNST index to produce a residual block for the current block and reconstructing the current block of the video data using the residual block and a prediction block for the current block.