The final merit list for the UPSC Civil Services is prepared based on candidates' combined performance in the PreliminaryMains, and Interview stages. First, candidates must qualify the prelims, after which only those who meet the cut-off proceed to the mains. The mains exam consists of written papers, with each candidate's scores calculated. Following this, candidates undergo an interview process, which evaluates their personality and suitability for public service. The scores from both the mains and interview are combined, and candidates are ranked according to their overall performance, resulting in the final merit list.