Students in England also face higher debts than counterparts in Canada, Australia and New Zealand, according to the Sutton Trust's Degrees of Debt study.
Students graduating in England last year, under the new £9,000 fees regime, owe an average £44,000, the study found.
And the Sutton Trust is concerned this figure could rise to more than £50,000 for poorer students when maintenance grants are abolished in September.
Debts in the US range from £20,500 for students studying at public or private non-profit universities, to £29,000 at private for-profit universities.
Average tuition fees in England are £8,800, compared with £6,600 at home-state, public universities in the US. Out-of-state and private universities are often more expensive in the US, but may have generous bursary schemes attached to them.
Sir Peter Lampl, chairman of the Sutton Trust and Education Endowment Foundation said today: “These debt levels are by far the highest in the English-speaking world and are more than double average debt levels at universities in the United States, where students study for four year programmes, rather than three.
"They impact on the ability of graduates to go to graduate schools, to afford a mortgage, the timing of having children and other major life decisions."