Methods, systems, and devices for overwriting at a memory system are described. A memory system may be configured to overwrite portions of a memory array with new data, which may be associated with omitting an erase operation. For example, write operations may be performed in accordance with a first demarcation configuration to store information at a portion of a memory array. A portion of a memory system may then determine to overwrite the portion of the memory array with different or updated information, which may include performing write operations in accordance with a second demarcation configuration. The second demarcation configuration may be associated with different cell characteristics for a one or more logic states, such as different distributions of stored charge or other cell property, different demarcation characteristics, different write operations, among other differences, which may support performing an overwrite operation without first performing an erase operation.