2.54 million uses of animals in scientific procedures in 2025

Cruelty Free International acknowledges the slight decrease in animal testing performed in laboratories in Great Britain, as reported by the Home Office today[1], but warns that the pace of change remains so painfully slow that cruel animal testing looks set to continue for many more decades to come.

There were 2,537,507 uses of animals in laboratories in Great Britain in 2025. This incremental change, a meagre 4% decrease from 2024, is not enough to meet public expectations or the potential to perform better science using modern, humane methods. This highlights the urgent need for the government – and new Prime Minister – to make progress in implementing its ‘Replacing animals in science: A strategy to support the development, validation and uptake of alternative methods’[2] which was published in November 2025.

The number of animals used in experimental procedures fell by 8% in 2025, to 1.32 million.

There was a 1% increase in the creation and breeding of genetically altered animals – those whose genes have been modified but have not then been used in further tests. In 2025 there were 1.22 million such uses of animals, this accounted for 48% of all 2.54 million uses.

Animals used in regulatory testing, including the standardised tests designed to assess the safety or effectiveness of chemicals, medicines and other products, and for routine production which uses animals to make biological products like antibodies, accounted for 10% of the total 2.54 million, a 22% decrease in 2024. 

712,699 animals were used in basic research, accounting for 54% of the total number of animals used in experiments and a 4% decrease on last year. This curiosity-driven research attempts to shed light on biological processes. Translational research, which attempts to develop treatments or cures for diseases, accounted for 26% (340,253, similar to that in 2024); and other areas of animal use, including higher education, species preservation and protection of the environment, accounted for 1% (18,309, a decrease of 45% on 2024).

Of the total 2.54 million uses of animals in 2025, 17% were considered by researchers to have caused moderate or severe pain and suffering to the animals involved, including long-term disease and even death during the experiment. These two categories involved a total of 439,764 animals.

The total number of experiments on dogs rose by 9%, to 2,889. There was a 15% increase in experiments on monkeys, to 2,236, a 15% decrease in the use of rabbits, to 5,291, and a 38% decrease in the use of guinea pigs, to 1,676. There was also an 11% increase in experiments on cats, to 91, and a 5% rise in the use of horses, to 12,101.

Mice and rats continued to be among the most frequently used animals in scientific procedures, with 1.8 million mice and 126,500 rats used in 2025.

The statistics also show that, despite progress in some areas, the full elimination of increasingly outdated tests is yet to be achieved and, in fact, a continuation for some tests has been observed for 2025. Cruelty Free International’s Replace Animal Tests (RAT) List[3] describes animal tests that are conducted in Britain despite having approved non-animal replacements and whose abolition could save over 80.000 animals every year. The number of eye irritation and corrosion tests fell to zero, from three in 2024; skin sensitisation tests on mice decreased by 79% to 31; and skin irritation and corrosion remained at zero in 2025.

The number of uses of animals in the testing of chemicals, including ingredients used in everyday consumer products, fell by 45% in 2025, to 33,088. Other sectors which used animals included the testing of human medicines (111,213), veterinary medicines (86,858), plant protection products, such as pesticides (12,681) and tests for food production (1,449). There were no animals used in the testing of ingredients exclusively used in cosmetics products in 2025.

Recent analysis carried out by Cruelty Free International shows that after six months following the publication of the UK’s Strategy, progress against the commitments set out is still at an early stage, with some signs of fragmented and largely procedural efforts. The report, ‘From Promise to Proof?’, warns that there is currently limited evidence available of government activity which will drive the system-wide change necessary to significantly reduce the number of animals used in Great Britain.

Dr Emma Grange, Cruelty Free International’s Director of Science and Regulatory Affairs, said: “With 2.54 million uses of animals in British laboratories in 2025, a meagre 4% decrease from 2024, the rate of decline remains painfully slow. We ask that the government now starts to show the sort of bold leadership and ambition promised in its strategy, and takes the opportunities it created for early wins, which are always crucial to the success of any long-running plans. A change in prime Minister must be taken as an opportunity to boost delivery and speed up progress.

“Taking definitive action now could mean that this is one of the last years where the use of animals is anywhere near this level. The British public are ready for animal testing to end and, with a combination of political leadership and scientific development, this can be delivered. The focus must be on the transition to exclusive use of non-animal scientific methods, some of which have already been shown to perform at least as well, or better, than tests on animals. Any cruel animal test is one too many and we will continue to fight for zero animal experiments in Great Britain.”