The squeeze on household and business finances has got tighter with the numbers behind in their repayments rising to the highest level in four years, according to credit reporting firm Centrix.

Its latest monthly report shows 426,000 people behind in their payments, up from 411,000 in April. That represents 11.7 percent of active consumer borrowers, and is the highest since March 2019.

The level of mortgage arrears increased to 1.3 percent, the highest since 2020, with rises also for buy-now-pay-later, consumer, auto, and unsecured personal loans.

Centrix managing director Keith McLaughlin said hopes that April's decline showed households getting on top of debts and coping with higher interest rates had been dashed, and the latest numbers showed economic realities.

"Some Kiwi households and businesses are walking an economic tightrope," he said. "While homeowners contend with rising mortgage interest rates and the financial squeeze, business owners are grappling with downturned activity and spending."

He said the rise in arrears for unsecured loans to 10 percent pointed to consumers borrowing just to make ends meet in the face of rising costs.

Overall, credit arrears were 4 percent higher than a year ago.

McLaughlin said debt pressures were also building for the business sector, with credit defaults up for most industries, notably 22 percent on a year ago for the property and rental sector, and around 16 percent for construction, retail, and hospitality.

"It's no secret a recession was the Reserve Bank's goal to help curb spending. What remains to be seen is how the rest of 2023 plays out for consumers and businesses on the front line."

Credit demand was mixed with a 27 percent fall in mortgage lending on a year ago, tracking the decline in the property market, but there was an increase in other consumer lending, especially vehicle loans.

The number of business liquidations dipped slightly on April, but compared to a year ago were 35 percent higher, which McLaughlin said reflected a tougher attitude to tax arrears by Inland Revenue and a decline in personal spending which was pressuring cashflow.