The two main highways out of Wellington are also expected to be heavily congested.
State Highway 1 on the Kapiti Coast looks heavy from tomorrow at 9.30am until 6pm and for a few hours every day until January 4.
And State Highway 2 at Rimutaka Hill is classified as heavy from Boxing Day from 10.30am to noon.
NZTA said the predictions were subject to change based on weather or other factors.
For real time information on the day, motorists can subscribe to OnTheMove or visit NZTA's Traffic and Travel information page, or call 0800 4 HIGHWAYS (0800 44 44 49).
The times have been calculated based on previous years' travel patterns for Christmas and New Year.
"Roads across Bay of Plenty/Waikato are always busy at this time of year as people visit family and friends and there are often delays, but if everyone allows plenty of time for their journey, drives to the conditions and plans ahead before leaving home the worst of the frustrations can be eased," says Niclas Johansson, the Waikato and Bay of Plenty State Highways Manager.
"Data from previous years shows state highways will be busy throughout the middle of the day all the way from the 23rd of December to the 4th of January, with particularly heavy times on individual routes and days."
Maria Lovelock, manager of Road Safety Education Limited, which runs road safety programmes for young drivers, reminded drivers they'd be sharing the road with not only cars but pedestrians, cyclists, heavy trucks, buses, campervans and vehicles towing boats or caravans.
"Getting behind the wheel of a car as a young driver or passenger is said to be among the most dangerous things a person will do in their entire life.
""Stop and think about what your family would do without you this Christmas and every Christmas to come, before you take risks on the road."
She urged parents to talk with their children about being safe on the roads.
"Where young people own less safe cars, parents could consider making the safer family car available for those higher risk trips such as peak holiday travel times.
"A little bit of planning can make a huge impact on safety - so hopefully we won't see an increase in road crashes this holiday season."
Check weather and road conditions, carry an emergency kit with items useful if you end up being stranded on the site of the road and make sure your car is serviced.
"Prepare your car by having it serviced, checking the tyres have plenty of tread and prepare yourself - rest before a long drive, plan the trip so you share the driving and take regular breaks to avoid fatigue," Lovelock said.
"If you're travelling with pets make sure they are restrained - for everybody's safety and never leave them in a hot car."
Auckland Airport says travellers should allow an extra half hour to make their way through the busy terminal today as it was "one of our busiest international travel days this summer".
Coastguard has also strongly urged boaties to be vigilant this summer and know the basic safety rules when going out on the water.
There were 19 boating-related fatalities last year.
Heaviest traffic times
State Highway 1, south of Auckland (Takanini)
Southbound
Dec 23: 11am-10pm
Christmas Eve: 10am-8pm
Christmas Day: 10am-2.30pm
Boxing Day: 9.30am-2.20pm
Dec 27: 9.30am-3pm
Dec 28: 10am-noon
Northbound
Jan 3: 12.30pm-4.30pm
Jan 4: 1pm-4pm
State Highway 1, north of Auckland (between Puhoi and Wellsford)
Northbound
Christmas Eve: 3pm-6pm
Christmas Day: 10am-1pm
Boxing Day: 9am-3pm
Dec 27: 8.30am-6.30pm
Dec 28: 10am-4.30pm
Dec 29: 11am - 4pm
Dec 30: 9.30am-5pm
Dec 31: 11.3am-3.30pm
Jan 4: noon-1.30pm
Southbound
Jan 1: 10am -6pm
Jan 2: 10.30am-8pm
Jan 3: 11am-5pm
Jan 4: 11am-1.30pm
State Highway 2, towards Coromandel, Tauranga (Maramarua)
Eastbound
ChristmasEve: 3pm-7pm
Boxing Day: 9.30am-1pm
Dec 27: 9am-3pm
Dec 28: 9.30am-12.30pm
Dec 29: 11am - 4pm
Dec 30: 9.30am-5pm
Dec 31: 11.3am-3.30pm
Jan 4: noon-1.30pm
Westbound
Jan 1: 1pm-7pm
Jan 2: 11am-7.30pm
Jan 3: noon-6.30pm
Jan 4: 12.30pm-3pm
State Highway 1, north of Wellington (Kapiti Coast)
Southbound
Dec 23: 9.30am-6pm
ChristmasEve: 9am-4pm
ChristmasDay: 10.30am-12pm
Boxing Day: 10am-4pm
Dec 27: 10.30am-5.30pm
Dec 28: 10.30am-5.30pm
Dec 29: 10am-5pm
Dec 30: 10.30am-5.30pm
Dec 31: 11.30pm -4pm
Jan 1: 3pm-4pm
Jan 2: 11am-8pm
Jan 3: 11am-7.30pm
Jan 4: noon-6pm
Northbound
Dec 23: 8.30am-6.30pm
ChristmasEve: 8.30am-5.30pm
ChristmasDay: 9.30am-1pm
Boxing Day: 8.30am-3pm
Dec 27: 9am-5.30pm
Dec 28:9am-4pm
Dec 29: 8am-6pm
Dec 30: 9.30am-4.30pm
Dec 31: 9.30am-4pm
Jan 1: 11am-3pm
Jan 2: 10am-3pm
Jan 3: 10am-3.30pm
Jan 4: 10am-12.30pm
State Highway 2, north of Wellington (Rimutaka Hill)
Northbound
Boxing Day: 10.30am-noon
Dec 27: 10am-noon
Dec 28: 10.30am-noon
Jan 2: 9am-12.30pm
Southbound
Jan 2: 3pm-7pm
Jan 3: 4pm-5.30pm
- Source: NZTA