Methods, systems, and devices for wireless communications are described. A user equipment (UE) may support communicating sidelink feedback for a transport block communicated over multiple transmission time intervals (TTIs). For example, a first UE may receive one or more repetitions of a transport block from a second UE over a sidelink channel, where the one or more repetitions of the transport block may together span multiple TTIs. Each of the first UE and the second UE may identify at least one of the TTIs and may determine one or more resources of a sidelink feedback channel based on an index of the at least one TTI. The first UE may transmit, to the second UE, feedback pertaining to the reception of the one or more repetitions of the transport block over the determined one or more resources.