The Australian share market has been unable to extend its rally into a third day, fading in the late afternoon to close marginally lower despite a strong day for the banking sector.

The S&P/ASX200 benchmark index finished Wednesday down five points, or 0.09 per cent, at 5,775 points, while the All Ordinaries index was also down five points, or 0.08 per cent, at 5,884.9.

The Australian dollar was buying 66.45 US cents, up from 65.91 US cents at the close of trade on Tuesday.