The Big Butterfly Count is a nationwide citizen science survey aimed at helping to assess the health of our environment. It was launched in 2010 and has rapidly become the world’s biggest survey of butterflies.
The Big Butterfly Count 2026 takes place between 17 July and 9 August.
How to take part
Simply count butterflies for 15 minutes during bright (preferably sunny) weather during the Big Butterfly Count dates. This time of year is chosen because most butterflies are at the adult stage of their lifecycle, so more likely to be seen. Records are welcome from anywhere: from parks, school grounds and gardens, to fields and forests.
A list of target butterfly and day-flying moth species is provided for those species they’d like you to count. By restricting the list it minimises counting error and therefore gives a clearer view of actual butterfly numbers across the country.
You can record your sightings and view all the counts on the interactive map. If you spot species which are not on the target species list you can still record them using the iRecord Butterflies App.
You can find the full information on the Big Butterfly Count website.
Butterfly Conservation
The survey is run by the charity Butterfly Conservation, a member and valued data partner of the NBN Trust.
You can view Butterfly Conservation data on the NBN Atlas. We hold more than 47 million species occurrence records from Butterfly Conservation making them the third highest contributing data partner to the Atlas!