"If you can plan your travel outside of these times you'll be giving yourself a much less stressful start to the weekend and help ease congestion levels for everyone else."
One of the busiest highways will be the Northern Gateway Toll Road on State Highway 1 north of Auckland, which had more than 21,000 trips a day during previous anniversary weekends.
Waikato journey manager Liam Ryan said: "Roads across Bay of Plenty-Waikato will be busy with people visiting family and friends on these long weekends and these big events are likely to add to the numbers."
"So we urge travellers to allow plenty of time for their journeys, drive to the conditions, and plan ahead before leaving home."
The NZTA website has interactive maps showing the busiest routes and times.
"Our hotspots information is based on previous years' travel patterns on Anniversary Weekend and we expect that will be mirrored for the weekend to follow with Waitangi Day falling on the Monday," Ryan said.
"They are predictions and are subject to change based on weather or other factors, and we encourage people to check the travel section of our website or our social media pages so they can know the road conditions before they start their journey."
Traffic hotspots
SH1 Whangarei
• Northbound:
Friday 11am-7pm
Heaviest 2pm-6pm
• Southbound:
Friday 7am-4pm
Monday 10.30am-3.30pm
SH1 Puhoi-Wellsford
• Northbound:
Friday 11am-8pm
Heaviest Noon-6.30pm
Saturday 8.30am-3pm
• Southbound:
Monday 9.30am-6.30pm
Heaviest 10.30am-5pm
SH1 Takanini
• Southbound:
Friday 9.30am-9pm
Heaviest 11am-8pm
Saturday 7.30am-5pm
Heaviest 8.30am-1pm
Sunday 8am - noon
Heaviest 9am-11am
• Northbound:
Sunday Noon-7.20pm
Heaviest 2pm-6.30pm
Monday 10.30am-7.30pm
Heaviest 11.30am-6pm
SH1 Karapiro
• Eastbound:
Friday 1pm-7pm
Heaviest 2pm-6pm
Saturday 8.30am-12.30pm
Heaviest 9.30am-11am
• Westbound:
Monday 11am-6pm
Heaviest 3.30pm-5pm
SH1 Taupiri
• Southbound:
Friday 10am-9pm
Heaviest 11.30am-6pm
Saturday 8.30am-2.30pm
Heaviest 9.30am-1pm
Sunday 9.30am-12.30pm
• Northbound:
Friday 12.30pm-6.30pm
Heaviest 2pm-5.30pm
Sunday 2pm-7pm
Heaviest 4.30pm-6pm
Monday 1-.30am-6.30pm
Heaviest 12.30pm-4.30pm
SH2Maramarua
• Eastbound:
Friday 10am-10pm
Saturday 8am-3pm
Heaviest 9.30am-2pm
• Westbound:
Sunday 2pm-6pm
Monday 10.30am-8.30pm
Heaviest 11.30am-7.30pm
SH2 Paeroa-Tauranga
• Eastbound:
Friday 2pm-8pm
Saturday 10.30am-2.30pm
• Westbound:
Monday 10am-5.30pm
Heaviest 11am-3.30pm
SH3 Kaimai
• Eastbound:
Friday 2pm-7pm
Heaviest 4.30pm-6pm
Saturday 10am-3pm
Sunday 10.30am-noon
• Westbound:
Monday 10.30am-6pm
Heaviest 11.30 am-5pm