The Aigion fault is one of the youngest major normal faults in the Gulf of Corinth, Greece, and has an immature displacement profile. Based on geometry, slip rate, and comparison with regional faults, we estimate the fault system length as ∼10 km. The slip rate of the fault system is ∼3.5 ± 1 mm/yr, decreasing to ∼2.5 ± 0.7 mm/yr close to its eastern tip. Complex fault geometry and displacement profiles on the shelf east of Aigion are consistent with the latter as the eastern tip location. Analysis of slip on this fault system and the established fault to the south (western Eliki fault) suggests that slip was transferred rapidly but not homogeneously between the two faults during the period of contemporaneous activity. Together with a lack of evidence of lateral propagation at the eastern fault tip in the past 10–13 k.y., we suggest that the fault developed and established its current length rapidly, within its 200–300 k.y. history. These results contribute to our understanding of the process of northward fault migration into the rift and the development of new normal faults.