Gastrointestinal nematodes, including Haemonchus (H.) contortus, have a notable impact in terms of impaired production, high fatalities, and substantial economic losses, affecting small ruminants in tropical countries, including Pakistan. The irrational use of synthetic chemicals has fueled anthelmintic resistance, particularly in H. contortus, as a formidable challenge, prompting a search for alternative treatment strategies. This study evaluated the anthelmintic potential of leaf extracts of three forage plants, including Leucaena leucocephala, Moringa oleifera, and Acacia ampliceps, against various developmental stages of H. contortus. Phytochemical screening revealed the presence of secondary metabolites in the extracts. In vitro assays were performed to evaluate the anthelmintic efficacy of the extracts on the inhibition of egg hatching, larval paralysis, and adult worm motility following the guidelines of the World Association for the Advancement of Veterinary Parasitology, while Albendazole was used as a positive control and PBS as a negative control. The highest concentrations of tannins and flavonoids in Acacia ampliceps and phenolic compounds in Leucaena leucocephala were detected in the extracts as major secondary metabolites. All the tested extracts showed significant time- and dose-dependent responses to various stages of H. contortus. The ED₅₀ values showed that the lowest dose of Leucaena leucocephala (0.285), Moringa oliefera (0.81), and Acacia ampliceps (0.245) inhibited egg hatching and larval and adult motility, respectively. Extracts of Leucaena leucocephala exhibited significant inhibition of egg hatching (70.3%), whereas Moringa oliefera showed maximum percent inhibition (66.6) of larval motility. These findings suggest that these plants, traditionally used by local healers in Pakistan, may possess antiparasitic properties, encouraging further studies on the relationship between phytochemicals, extraction methods, and in vivo trials to explore their anthelmintic efficacy.