"Everyone seems to be pretty patient and seems to be enjoying themselves and getting a good bargain."
Most of the Mt Wellington mall opened at 8am and will close at 9pm with the Warehouse closing at 10pm and K-Mart trading 24-hours until New Year's Eve.
Last year the mall attracted about 50,000 shoppers in one day.
At The Base in Hamilton an extra carpark has been opened with a shuttle bus to the mall to cater for the influx of shoppers.
Centre manager Simon Betts said even though parking was almost at capacity there had been no incidents or complaints, and traffic flow into the mall was steady.
The extra carpark would be open for Boxing Day only.
Many stores were carrying heavily discounted stock such as Briscoes which had between 30 to 70 per cent off, including dinner sets for $10 and entire outdoor furniture settings for under $900.
"There's been some pretty reasonable discounts and it's definitely reflected with the volume of people here," Betts said.
The mall closes at 6pm today.
Many shoppers were out cashing in on Christmas vouchers and money given yesterday in lieu of gifts.
It comes as $297.5 million was spent on the traditionally busiest shopping day of the year, Christmas Eve.
That frenzy beat Black Friday sales of $253m and was almost five times the amount spent last Boxing Day, $63.8m.
Betts said mall operators would not know the official takings for Boxing Day until figures are released next month, with breakdowns only given by the month.
Paymark would release figures on December 28, but said on Christmas Eve shoppers made 199 transactions per second at the day's peak, 12:09pm.
Paymark handled more than 679,000 transactions an hour that day.
Online transactions were also not to be underestimated, with Boxing Day sales applying to most retailer's websites as well.
Meanwhile, making unplanned purchases was a danger, according to Auckland University's senior lecturer in marketing, Dr Bodo Lang.
"This is a really common occurrence - people get into what's called the flow, they just get into a purchasing mania and buy far more than they planned to buy," Lang told Newstalk ZB's Tim Dower.
He said there "absolutely" were genuine bargains to be had, such as with bikes - where 2020 models launched in summer meant 2018 and 2019 stock would often be on sale despite being in perfect condition.
"Of course there is a danger also of being lured in and buying things that may not be on sale, or where the sales advantage is quite insignificant so it's just a small reduction."