Seminal fluid induces major changes in the uterine transcriptome immediately after mating, inducing cytokine and immune cell changes that initiate maternal immune tolerance for pregnancy. However, whether and how seminal fluid contact at mating affects endometrial gene expression subsequently in the peri-implantation phase is unclear. To address this knowledge gap, we utilised high-throughput RNA-sequencing to identify genes and pathways regulated by seminal fluid components in the endometrium of C57Bl/6 female mice on day (d) 3.5 post-coitum (pc) after mating with intact (INT), vasectomised (VAS), seminal-vesicle-deficient (SVX), or SVX/VAS BALB/c males (n=3-4/group). RNA-sequencing and Ingenuity Pathway Analysis revealed that compared to SVX/VAS-mated females, the T Cell Receptor (TCR) Signalling Pathway was the top pathway activated in INT-mated females (Z-score=3.2). Interestingly, γ/δ TCR genes Tcrg-C1 and Trdc (2.8- and 2.2-fold increase), and genes associated with γ/δT cell function including Il7r and Blk (2.6- and 3.1-fold increase), were amongst the top differentially regulated genes. These changes were mainly driven by seminal plasma, as mating with VAS males induced a similar increase. The γ/δT cell population in the uterus was then assessed using flow cytometry on d3.5pc, with virgin females as estrous control (n=11-12/group). The γ/δT cell population in the uterus was expanded after INT or VAS mating by 8.3-and 10-fold compared to virgin females, with 22.4- and 21.9-fold more γ/δT cells expressing the proliferation marker Ki67. This increase was not evident in females mated with SVX or SVX/VAS males. Together, this study demonstrates that seminal fluid contact alters the endometrial transcriptome at implantation, and identifies expansion of a resident γ/δT cell population as a dominant element of this response. This increase in γ/δT cell number in response to semen has potential to modulate receptivity to embryo implantation, but future studies are required to define its exact contribution to reproductive success.