The Sensex fell on Tuesday, retreating from a three-year high hit earlier in the session, as blue chips declined ahead of the October 17 deadline to lift the US debt ceiling. Lenders led decliners after data showing higher-than-expected headline and retail inflation on Monday sparked concerns the central bank would raise interest rates this month. The Sensex fell 0.3 per cent, or 59.92 points, to end at 20,547.6, earlier hitting its highest intra-day level since November 2010. The Nifty fell 0.4 per cent, or 23.65 points, to end at 6,089, snapping its five-day winning streak.