Methods, systems, and devices for wireless communication are described. A wireless device may transmit feedback, such as hybrid automatic repeat request (HARQ) feedback for groups of code blocks rather than for an entire transport block or individual code blocks. The wireless device may transmit an acknowledgement (ACK) or negative-acknowledgement (NACK) to provide feedback for each code block group of a set of code block groups. An ACK may indicate that code blocks in a code block group were successfully decoded, and a NACK may indicate that at least one code block in a code block group was not successfully decoded. Wireless devices may support several techniques for grouping code blocks for feedback reporting to allow for efficient retransmissions and limited overhead. Different grouping schemes may be employed depending on system constraints, device capability, link conditions, or the like.