Australians lack preparation with travel money.

According to the Commonwealth Bank Travel Money Report, the average Australian overspends by more than $235 of their travel money than they had intended to when on an overseas holiday.

In total Australians overspent by more than $911 million on their international holidays each year. According to the Commonwealth Bank, the slip up is most likely due to lack of planning and budgeting with holiday funds before heading away that caused the budget blow outs.

"Only a fraction of holiday-makers set a daily or overall holiday spending budget, which makes tracking spending all the more difficult," said Commonwealth Bank acting executive general manager or retail products and customers, Clive Van Horen.

The report found that travellers were most likely to overspend on shopping for clothes and souvenirs, followed by food and drink, accommodation, transport and entry fees to attractions and events.

31 percent of travellers failed to organise their travel money at least one week before departure and once at their destination many lacked knowledge on exchange rates, the types of cards accepted or the fees for the use of an ATM.

Travellers looking for the best deals for their overseas spending money can compare travel money options on Mozo.

Have a question about travel money? Ask us here.