A report conducted by KPMG has revealed that Australian mobile carriers charge too much for international roaming.

The report was commissioned by the federal government owing to perceptions that the international roaming rates charged by Australian carriers are too expensive, due in part to overly high profit margins.

According the KPMG report, roaming margins are on average 300 percent higher than the margins for standard calls.

Although roaming rates vary wildly by country, the average roaming rate for Australian customers is $2.75 per minute, even though it only costs carriers an average of 46 cents per minute to place a call.

Geographical location seems to have little effect on roaming rates - it costs more for an Australian to roam in New Zealand than it does to roam in the UK or the US.

And the most expensive Australian rate is charged to Vodafone customers roaming in Indonesia, where it costs $5.00 per minute to place a call back home.

But Vodafone also offers the cheapest roaming rate – roaming in Singapore on the carrier costs less than $1.00 per minute.

Australian roaming rates are on average higher than Asian and North American rates, but lower than the average European roaming rates.

The Australian Mobile Telecommunications Association (AMTA) strongly criticised the report, stating it contained errors, methodological flaws and limited data.