Dogs Trust and Cats Protection have joined forces in a pet neutering campaign.
A leaflet campaign in Northern Ireland and Wales will target more than 530,000 low-income households over the next month.
"We believe that with this partnership we will be able to maximise the spend of both organisations and increase the impact of the campaigns," said Elvira Meucci-Lyons, Dogs Trust head of campaigns.
Both charities were running neutering schemes in the north-east. Meucci-Lyons said working together enabled them to appeal to more people.