Forget the Tardis or Star Trek. Samoans have a simpler answer to changing the calendar – and warping the dateline is so much easier than time travel.

But those who routinely thank goodness it's Friday in the Pacific islands state may be less happy. This year, 30 December is disappearing as Samoa skips the day entirely.

The country that has been able to say it sees the world's last sunset of the day is about to edge ahead of Tonga as the place where 2012 begins.

The decision to change Samoa's place in the world temporally reflects a new business order. It will be on the same day as New Zealand, Australia and China.

"In doing business with New Zealand and Australia, we're losing out on two working days a week," the prime minister, Tuilaepa Sailele Malielegaoi, said in April when the plan to push the clocks 24 hours forward was announced. "While it's Friday here, it's Saturday in New Zealand and when we're at church on Sunday, they're already conducting business in Sydney and Brisbane."

He suggested Pacific tourists could celebrate the same day twice, because American Samoa next door stays on the other side of the dateline.

"You can have two birthdays, two weddings and two wedding anniversaries on the same date – on separate days – in less than an hour's flight across [the ocean], without leaving the Samoan chain," the prime minister enthused.

The Westpac Samoa bank had good news for its customers, too. "This is a very significant day in the history of Samoa and for some time now we've been planning and programming our systems to deal with the event," said Michael Mjaskalo, its general manager, according to the Samoa Observer.

"Customers can be assured that Westpac will not charge interest on credit and loan facilities for the missing day. However, we will pay the appropriate interest on interest-bearing deposits for the missing day even though we are not obligated by law."

Two years ago, Tuilaepa switched Samoan driving from the right to the left side of the roads, in line with Australia and New Zealand. The move meant expat Samoans could send used cars home to their relatives.

Samoa has crossed the international dateline before. In 1892, its then king was persuaded to fall in step with American ships sailing west to San Francisco. That shift gave the Samoan calendar an extra day that meant consecutive fourths of July.