Spokesman Paul Brislen said the strong pre-Christmas period was also possibly an influence on the lower-than-usual Boxing Day patterns.
"As per usual, the busiest days of the year were the immediate days before Christmas Day.
"Spending on the two days before Christmas Day was up 10.4 per cent on last year for the same group of merchants, with the busiest day being Wednesday, two days before Christmas."
Christmas Eve spending of $75m was well up on 2019 when $70m was spent.
Looking across the pre and post-Christmas period, annual spending for the five weeks ending Sunday, December 27 was up 5 per cent on last year, which included a strong start over the Black Friday four days of sales.