Like many major retailers, supermarkets offer savings schemes.

Countdown, for example, sells Christmas Club vouchers through the year. A 5 percent bonus is available when vouchers are bought before 1 December and used through December and January.

Shoppers at New World and Pak’nSave can sign up for a Christmas Club card and then top it through the year. A bonus is available if the saved money is not used until December. The extra amount varies depending on when the money has been deposited: customers get an extra 32 cents for every $5 deposited between 1 December the year before and February 29, an extra 27 cent deposited between March and May, 22 cents between June and August, 17 cents between September and the end of November.