This article documents the timeline of transmission of COVID-19 during the COVID-19 pandemic in New Zealand throughout 2021. The following dates and times are in New Zealand Daylight Time (UTC+13) until 3 April and New Zealand Standard Time (UTC+12) from 4 April. On 17 August 2021 at 11:59 pm, after a report of a new community case presumed to be infected with the Delta variant of the virus earlier that day, New Zealand moved to alert level 4, entering a nationwide lockdown for a minimum of three days.