George St shops were packed with customers, and Michael Hill Jeweller staff reported a queue of about 20 people before the shop opened.
The first bargain-hunter had arrived at 5am.
A queue had also formed at The Warehouse in South Dunedin.
Outside The Warehouse, the Taane family were leaving with a trolley full of goods, having cashed in vouchers they received as presents on Christmas Day, and picked up a cheap vacuum cleaner.
"We do it every year. We try to get in early and get the bargains," Jamie Taane said.
Early reports of sales nationally suggested the number of transactions was comparable with last year, the New Zealand Press Association reported.
Eftpos-provider Paymark chief executive Simon Tong said that by 4.30pm on Boxing Day shoppers had spent $77 million in electronic transactions, with 77 transactions a second between noon and 1pm.
On Christmas Eve, shoppers nationally spent $226 million in electronic transactions, $10 million more than last year.
Glassons was wall-to-wall with young shoppers, and third-in-charge Rebecca English said things had been "busy from the start".
Arthur Barnett duty manager Yvette Billot said it had been a "great day" in the store.
"There were so many people in town.
"They came in on a mission . . . they basically decided they were buying something before they left the house," she said.
Stores outside the main shopping street were also busy, with long queues and a full car park at Harvey Norman, and many shoppers at Crawford St outlets.
Otago Chamber of Commerce chief executive John Christie said it was hard to know how the transaction numbers compared with other years until the statistics came in, but it did appear to have been a "pretty strong day of retailing".
