Those travelling on the roads over the next few days are being told to plan their journeys and keep an eye on alerts to avoid long delays.
Fine weather conditions are also resulting in more people hitting the road on trips to the beach and out of town; while others start to head back in time for work next week.
Traffic was heavy this afternoon, around 1pm, going north on State Highway 1 to Pūhoi.
It was also heavy entering Warkworth; but otherwise free-flowing going towards Wellsford.
The NZTA said: "Traffic is expected to be busy through this area between 9.30am and 6pm for northbound traffic and between 9am and 9pm for southbound traffic today.
"Road users are advised to expect delays and allow extra time for their journeys when travelling through this area.''
A car fire on SH60 in the Motueka and Tasman area closed the road entirely about 2.30pm. There were delays as emergency crews worked to clear the site about an hour later.
A serious crash on SH1 Rangitata, in Canterbury, caused some delays just after 1pm.
Emergency services were called to the intersection of SH79 and lanes were operating under a stop-go system.
People heading north on that road were being told to turn left after the Orari River Bridge onto Geraldine-Arundel Rd to get back onto SH1.
The NZ Transport Agency is telling people to check its dedicated Holiday Journeys page, which shows peak congestion travel times on various main roads and highways around the country.
The Journeys Planner site is also a useful tool that lets people enter their journey - where they are travelling to and from - and which then shows the quickest route, travelling times and any congestion or road works happening along the way.
In the Waikato and Bay of Plenty areas, road authorities have warned that traffic delays will be expected on SH2 at Katikati and Waihī, and on SH25 at Tairua over the next few days, as holidaymakers move about.
In the Wellington area, people are being told to be prepared for traffic delays on SH1 around Ōtaki.
Further south, in Otago and Southland, motorists were reminded of it being the peak season for "summer ice".
"During long spells, dust, dirt and oil build up on the road,'' the NZTA said.
"When it rains, the road becomes greasy - making it dangerously slippery. The greatest risk is shortly after rain starts.''
Holidaymakers in those areas can expect some traffic delays on highways around Central Otago district this week.