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I have a question and a concern regarding transit visa requirement for Indian Citizen travelling back to US via London while on F 1 Visa. I have one semester left and I am visiting my family this winter. I will be coming back on 19th of January from New Delhi to Boston via London. I have visited UK's official website but I am not clear with conditions for Transit visa considering that I have a connecting flights with same airline (landing on LHR on 19th January at 5:40 pm and schedule to take off on 20th January at 9:20 am). It would be great If somebody here can comment on this and provide me with some detailed information about this.