The number of people filing for bankruptcy or protection from bankruptcy is reportedly up by 25% compared with last year.
Veda Advantage, which holds files on 97.5% of the population with credit histories, says 4,751 people filed for either bankruptcy or no asset procedures this year.
The credit-checking agency, formerly known as Baycorp, says several other indicators of financial stress have increased in the last month.
It says the average amount owed by creditors in default referred to it has also doubled compared with the same time last year.
Veda says a fall of 26% in the number of people applying for credit during the month of November - traditionally a busy time in the lead-up to Christmas - is a worrying sign for the retail sector.