Maintenance of male fertility is dependent on spermatogonial stem cells (SSCs) that self-renew and generate differentiating germ cells for production of spermatozoa. SSC function is dependent on growth factors produced within the testis microenvironment plus cellular factors that regulate gene expression within SSCs and modulate responses to growth factor stimulation. Importantly, germline cells are sensitive to genotoxic drugs and patients receiving chemotherapy often become infertile. SSCs surviving treatment can mediate germline recovery but the cellular pathways and transcriptional regulators driving SSC regenerative responses remain poorly understood. Our studies have focused on understanding the roles played by growth factor-regulated signalling pathways and downstream effectors in controlling the transcriptional state and function of SSCs under homeostatic and regenerative conditions through use of mouse models and single cell RNA-Seq approaches. We find that SSCs mediating germline regeneration adopt a unique cellular state associated with alterations in PI3K-mTORC1 signalling when compared to SSCs of steady-state tissue. While chronic stimulation of PI3K-mTORC1 signalling is detrimental to SSC maintenance in undisturbed tissue, transient activation of this pathway was required to promote the SSC regenerative response. Concerted inhibition of growth factor signalling, including the PI3K-mTORC1 pathway, in SSCs resulted in pronounced defects in germline recovery after damage. Moreover, the transcription factor and cell cycle regulator FOXM1 was found to integrate diverse signalling inputs to support SSC regenerative capacity. Combined, our data demonstrate key instructive roles for microenvironmental growth factors and PI3K-mTORC1 signalling in defining distinct transcriptional states of homeostatic and regenerative SSCs.