Police appealed for information to identify a male in connection with a racially aggravated assault outside East Croydon railway station at 6.45pm on 18 December 2021.
The victim, a 31-year-old woman, had her hair pulled and was assaulted during the incident.
On Sunday, 13 February a 16-year-old male attended a south London police station and was arrested on suspicion of racially aggravated assault. He remains in custody.
Enquiries into the circumstances continue.