How to Budget a Trip from Australia

Trip budgets fail in a predictable way. The flights get priced exactly, the accommodation gets priced roughly, and everything else becomes a single number someone picked because it sounded about right.

Splitting the trip into four blocks fixes that, because each block is something you can look up.

Fixed costs come first: flights, accommodation, insurance, visas and any passport renewal. These are knowable to the dollar before you leave, and they make up most of the total on a short trip.

Daily costs come second: food, local transport, entry fees and the small things. Multiply a realistic daily figure by the number of days and resist the urge to round down.

Transport between places is the third block and the one most often folded into the daily figure by mistake. Rail passes, domestic flights and car hire belong on their own line because they scale with your itinerary rather than with your days.

The fourth block is the buffer. Ten per cent of the other three covers a missed connection, a medical excess or a change of plan.

Those figures come from our costed destination guides for Bali, Japan and a New Zealand campervan trip.

Foreign transaction fees are the largest of them. At the 3 per cent most Australian banks charge, $4,000 of overseas spending costs $120 in fees alone, plus about $5 for every ATM withdrawal.

Tourist levies and departure taxes add more. Bali charges every visitor a levy on arrival, and several countries collect a departure tax that is not in the airfare.

Then there is the trip either side of the flight. Airport parking, a taxi at each end and a night near the airport before an early departure add up to a few hundred dollars that nobody puts in the spreadsheet.

Divide the total by the months until departure and treat it as a fixed cost, the same as a bill. Our budget planner works out what that leaves you each month once your existing commitments come off.

Booking the flights early does two useful things. Fares tend to sit lower four to six months out, and paying the largest single cost up front means the remaining months only have to cover the rest.

Only on a balance you clear each month. Interest at 20 per cent or more turns a $4,000 trip into a considerably more expensive one, and no points return covers that.

Where a card earns its place is in the protections. Chargeback rights on a cancelled booking and the travel insurance some cards include are worth having, provided you pay the balance off.

Fixed costs, daily costs, transport between places, and a ten per cent buffer. Four numbers you can look up beat one number you guessed.

Work out the total before you book anything, then decide whether the trip you have planned is the trip you can afford. Adjusting the destination or the season is easier now than adjusting the itinerary from a hotel room.

Sort the card you will spend on before you go. Our travel money card comparison covers the fees, and our frequent flyer guides cover whether points can take the flights off the budget entirely.