At Restaurants: 10–15 percent for the waiter.

At Hotels: $1 per bag (in either Australian or New Zealand dollars, depending on where you are); $10–$20 to the concierge for a favor; $1–$5 per day to the housekeeper, depending on how messy you are.

Guides and Drivers: $5 for cabdrivers; $20–$50 per person for a private guide; $5–$10 for a bus-tour guide; $25–$50 per day for a private driver.

Who Else? 10–15 percent for beauty and spa treatments; tip Aboriginal and Maori guides exactly what you would others.

Dollars Accepted? Tipping should only be done in local currency.

P.S. "Twenty years ago, you'd be fired if you accepted a tip," says Donna Thomas of New Zealand Travel. Since then, tipping has spread "because Americans forced it on people." Be discreet and prepared to have your tip refused, especially in New Zealand, where people are particularly reserved.

Source : CNTraveler.com