Lithium–caesium–tantalum (LCT) pegmatites are a critical source of economically viable lithium, yet their timing relative to orogenic cycles varies globally and strongly influences the formation and distribution of lithium mineralization in collisional settings. Recent advances in in situ Rb–Sr geochronology of lepidolite enable direct dating of Li-rich pegmatite systems, particularly when integrated with in situ U–Pb and Lu–Hf geochronology of associated mineral phases. This study presents new in situ Rb–Sr, Lu–Hf and U–Pb geochronological data combined with petrological modelling from an east–west transect across the southern Benin–Nigerian Shield to constrain the timing of granite emplacement, regional metamorphism and LCT pegmatite formation during the Pan-African orogeny. Peraluminous Pan-African granites crystallized between c. 625 and 575 Ma, followed by peak metamorphism at c. 550–530 Ma, as recorded by monazite U–Pb and post-kinematic garnet Lu–Hf ages. Subsequent cooling through biotite Rb–Sr closure temperatures occurred between c. 530 and 500 Ma. A lithium-rich pegmatite swarm in the central-western part of the transect yields a dominant lepidolite Rb–Sr age population at c. 543 ± 12 Ma, overlapping regional cassiterite U–Pb ages reported for LCT pegmatites elsewhere in the Benin–Nigerian Shield and interpreted to record lepidolite crystallization and/or late-stage isotopic equilibration during pegmatite evolution. Petrological modelling reveals a static, isobaric increase in geothermal gradient during peak metamorphism, indicating a late thermal pulse that post-dates deformation. These results suggest that rare-metal pegmatite formation and evolution were broadly contemporaneous with late Pan-African metamorphism and highlight the importance of late- to post-orogenic thermal and fluid-related processes in the development of LCT pegmatite systems.