The Australians, with man-of-the-match George Bailey smashing an unbeaten 49 off 20 balls, scored 195 for six after winning the toss in Sydney. (Agencies)
The home side then dismissed the psychologically-scarred tourists for 111 in the 18th over to sweep the series.
It marked the end of a disastrous 103-day tour for England, who lost the Ashes Tests 5-0 and the one-day international series 4-1, meaning Australia won 12-1 across the three formats.
In between the losses, the international careers of spinner Graeme Swann and coach Andy Flower have been ended.
The future is also uncertain for Kevin Pietersen, Matt Prior and Jonathan Trott while Alastair Cook's Test captaincy is far from certain.
"It's been good fun throughout the tour. We've been hugely disappointing, not at the races for three months, but you have to give credit to Australia," said England T20 skipper Stuart Broad.
"We've got a two-week break at home and then go to the Caribbean but we know we're a decent T20 side.
"We can now get together as a group for a decent period to work on specific things, improve and learn from this week.
"We've got a dangerous side. We've got to go to Bangladesh (for the world T20) with confidence and hopefully we can get some momentum in the Caribbean."
England, perhaps with their minds on the team's departure home in the hours after the Sydney match, surrendered limply to the Australian bowlers.
Eoin Morgan was the best of a bad lot with 34 off 20 balls as the Australian bowlers shared in the wickets.
Nathan Coulter-Nile and spinners Glenn Maxwell and James Muirhead each claimed two wickets.
The Australians, with man-of-the-match George Bailey smashing an unbeaten 49 off 20 balls, scored 195 for six after winning the toss in Sydney.