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Objectives Several studies have reported an elevated risk of cancer, including lymphoid malignancies (LM), among farmers, particularly in relation to pesticide use. Chloroacetanilides are among the best-selling herbicides in France. Recent data on carcinogenic mechanisms and animals studies have prompted the IARC to initiate a new monography in late 2025 focusing on 3 molecules, including alachlor. The aim of our study was to evaluate risk for specific LM subtypes in relation to exposure to chloroacetanilide herbicides within the French AGRIculture and CANcer (AGRICAN) cohort.Material and Methods We included 155,173 individuals enrolled between 2005 and 2007. The main LM subtypes considered were chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL), diffuse large B-cell lymphoma and multiple myeloma (MM). Incident cases were identified through linkage with French cancer registries. Exposure to 7 active ingredients of chloroacetanilides was estimated using the PESTIMAT crop-exposure matrix. Cox models with a 10-year follow-up and age as the time scale were used to estimate hazard ratios and 95% confidence intervals for ever vs never exposed, exposure duration and score for each LM subtype.Results We identified 22,858 chloroacetanilide users and 1,654 LM cases in our population. Among men (236 LM cases among chloroacetanilide users), we found some increased risks of MM, particularly for alachlor (1.41 [0.88-2.26]), metolachlor (1.44 [0.90-2.31])) and napropamide, for low and intermediate exposure categories (ranging from +67% to +100%). Higher risks of CLL/SLL were also observed in the first quartile of exposure scores for Alachlor and Metolachlor (+72% and +82% increases, respectively). Increased risks were also noted for other subtypes such as follicular lymphoma in association with specific chloroacetanilide molecules. Among female users, only 8 LM cases were recorded.Conclusion This study contributes new evidence to a limited body of literature on the association between chloroacetanilide herbicide exposure and the risk of haematological cancers.