The communications sector was the most sluggish in its bill payments, with an average payment term of 54 days - eight days longer than the national average.
Forestry businesses were the quickest to pay, with a 40-day average, followed by those in the mining industry, at 41.8 days.
Firms in the finance, insurance and real estate sectors took an average of 43.6 days to make payments, Dun & Bradstreet said.
Large firms were the slowest payers, with those employing 500-plus staff taking an average of 51 days to pay, up from 45 in July 2009.
Christchurch businesses took the longest to pay during the June quarter, with a 48-day average, followed by those in Auckland with 47.7 days and Wellington, at 47.1 days.