Objective: To investigate public attitudes in New Zealand towards the euthanasia of dogs and cats and to explore the factors that influence these views. Materials and Methods: Data were collected through a nationwide online survey conducted in 2019 as part of the Furry Whānau Wellbeing research project. The survey included questions about pet euthanasia, and respondents were asked to indicate their level of agreement with various statements. Results: Of 2293 respondents to the 2019 New Zealand Pet Survey, the majority (n = 1756) opposed euthanasia for stray, unwanted, or financially burdensome pets (76.7% and 90.2% disagree, respectively). In contrast, a slim majority (n = 1162) supported it for sick animals. Females were less likely to agree with euthanasia in most scenarios compared to males. Māori and New Zealander European respondents (n = 1790) showed higher levels of neutrality than other ethnicities regarding stray animals and lower levels of disagreement regarding financially constrained situations. Older respondents (65+) were more likely to support euthanasia for sick animals, while younger respondents (18–24) were less inclined. Higher education levels are correlated with increased neutrality towards euthanising stray animals and increased support for euthanising feral animals. Respondents with children were more likely to be neutral or to disagree with euthanasia in most scenarios. Those with rural upbringings were more accepting of euthanasia for stray and feral animals. A thematic analysis of 653 respondent comments revealed key themes: euthanasia was seen as complex and context-dependent, a humane last resort for suffering animals, but not for convenience. Respondents emphasised responsible pet ownership and a right to life, even for feral animals, advocating for alternatives such as trap-neuter-release. Conclusion New Zealanders largely view euthanasia as an ethically acceptable option for terminally ill or suffering animals but reject it when driven by convenience or financial hardship. Attitudes vary across demographic groups, highlighting the need for culturally sensitive education and policy. The findings align with Sustainable Development Goal 3 (Good Health and Well-being) and support broader discussions on responsible pet ownership, ethical decision-making, and animal welfare legislation.