Collision detection systems for detecting read-write collisions in memory systems after word line activation are disclosed. In one aspect, a collision detection system is provided. The collision detection system includes a collision detection circuit for each bit cell row of memory array. Each collision detection circuit is configured to receive a write and read word line signal corresponding to the bit cell row. The collision detection circuit is configured to detect a write and read word line signal pair being active for a write and read operation for the same bit cell row. The collision detection circuit is configured to generate a collision detection signal to notify clients associated with the memory system that a read-write collision occurred. Detecting the read-write collisions after read word line activation reduces or avoids overhead delays in the read path, as opposed to detecting read-write collisions prior to activation of the read word line.