Baby City has been fined $39,000 in the Auckland District Court for selling two models of cots that didn't comply with the safety standard.
The cots, Milano 3-in-1 Sleigh and Milano Phoenix, were sold between October 2014 and October 2015 without the required safety information.
Baby City agreed with the Commerce Commission, which brought the charges, to implement testing and quality control procedures to ensure all cots it sells comply with the standard.
The cot leaflets didn't inform users the recommended mattress size was designed to minimise the risk of limbs being caught between the mattress and the sides of the cot.
The commission's Antonia Horrocks said it was important those buying a cot received the information needed to ensure it was assembled and maintained correctly so it was safe for a baby or toddler.
“In this case the information leaflets for both cots were missing important safety information. This included the need to place the cot a reasonable distance from power points, and an incomplete warning on the necessary mattress size,” she said.