The financial sector has dipped for the second day in a row as traders realised losses ahead of the end of the financial year.

The benchmark S&P/ASX200 index was down 17.5 points, or 0.25 per cent, to 6,640.5 points at 1615 AEST on Wednesday, while the broader All Ordinaries was down 18.4 points, or 0.27 per cent, to 6,716.1.

The Aussie dollar is buying 69.73 US cents, from 69.60 US cents on Tuesday.