Wellington, Jan 4 NZPA - The holiday road toll remains about half of last year's figures as holidaymakers return home tonight after the Christmas and New Year break.

So far 12 people have died in accidents since 4pm on Christmas Eve, with the majority of the deaths happening between New Year's Day and today.

Twenty five people died during the same period last year.

The official Christmas/New Year break finishes at 6am tomorrow.

Police said that traffic appeared to be flowing smoothly as people make their way home after the break.

Earlier today the country's busiest one-lane bridge, Kopu Bridge, near Thames was congested, but traffic was free flowing by tonight, Inspector Cornelius Kluessien from northern police communications said.

"Most people are getting home now in time for dinner," he said.

In the only reported fatal accident today a woman was killed when her car crashed into a vehicle carrying a family of overseas tourists on the last day of their holiday in New Zealand.

The accident happened at Wenderholm Regional Park, north of Auckland. The tourists escaped with minor injuries.

Police said that the woman may have lost control of her vehicle on the road made slippery by recent rain.

Traffic was diverted for several hours while police removed the vehicles and carried out an examination of the scene.

The traffic was starting to build up north of Wellington tonight as motorists returned to the capital.

Southbound traffic north of Otaki on the Kapiti Coast was backed up about five kilometres, Sergeant Mark Oliver of central police communications said.

Holiday traffic in Canterbury was flowing freely, police said.