Sensex ended the session at 80,718.01, up 150.30 points or 0.19 per cent. The 30-share index started the session with a massive gap-up at 81,456.67 against the last session's closing of 80,567.71 on the GST reform announcement. Nifty closed at 24,734.30, up 19.25 points, 0.08 per cent.