The recruitment of signaling proteins into activated receptor tyrosine kinases (RTKs) to produce rapid, high-fidelity downstream response is exposed to the ambiguity of random diffusion to the target site. Liquid-liquid phase separation (LLPS) overcomes this by providing elevated, localized concentrations of the required proteins while impeding competitor ligands. Here, we show a subset of phosphorylation-dependent RTK-mediated LLPS states. We then investigate the formation of phase-separated droplets comprising a ternary complex including the RTK, (FGFR2); the phosphatase, SHP2; and the phospholipase, PLCγ1, which assembles in response to receptor phosphorylation. SHP2 and activated PLCγ1 interact through their tandem SH2 domains via a previously undescribed interface. The complex of FGFR2 and SHP2 combines kinase and phosphatase activities to control the phosphorylation state of the assembly while providing a scaffold for active PLCγ1 to facilitate access to its plasma membrane substrate. Thus, LLPS modulates RTK signaling, with potential consequences for therapeutic intervention. [Display omitted] • Phosphorylated RTKs undergo phase separation with downstream effectors • Phosphorylation-dependent multivalent interaction drives FGFR2-SHP2 phase separation • The FGFR2-SHP2 complex colocalizes PLCγ1 to its plasma membrane substrate • Enzymatic activities are regulated within the FGFR2-SHP2-PLCγ1 membraneless droplets Lin et al. demonstrate that phosphorylated RTKs undergo liquid-liquid phase separation upon the recruitment of downstream proteins. Focusing on the RTK FGFR2, this process is shown to modulate enzymatic activities within the subcellular membraneless compartment. [ABSTRACT FROM AUTHOR]