Salmonella uses a type 3 secretion system to inject virulence proteins into host cells during infection. These proteins modulate host cell machinery to facilitate bacterial uptake into vacuoles, where they can replicate intracellularly. A key feature of Salmonella invasion is the formation of actin-rich protuberances (ruffles) on the host cell surface that aid in bacterial uptake. However, the membrane source for ruffle formation and how Salmonella regulates membrane mobilization within host cells remain unclear. This study shows that Salmonella exploits pre-existing membrane reservoirs for the generation of invasion ruffles. These reservoirs are tubular compartments associated with the plasma membrane (PM) and are formed through the activity of RAB10 GTPase. Under normal growth conditions, these reservoirs contribute to PM homeostasis and are preloaded with the exocyst subunit EXOC2. During Salmonella invasion, bacterial effectors SipC, SopE2, and SopB recruit exocyst subunits from membrane reservoirs and other cellular compartments, allowing exocyst complex assembly and membrane delivery required for bacterial uptake. The findings reveal an important role for RAB10 in the establishment of membrane reservoirs and the mechanisms by which Salmonella can exploit these compartments during host cell invasion. Salmonella enterica serovar Typhimurium (STm) is a gram-negative intracellular bacterial pathogen that is a major cause of foodborne gastroenteritis in humans. These bacteria can rapidly invade host cells using a type 3 secretion system (T3SS) encoded by Salmonella pathogenicity Island (SPI-1). SPI-1 T3SS effectors are known to promote the delivery of membrane to the invasion site via the exocyst complex, contributing to the formation of ruffles that envelop bacteria. However, the membrane source required for exocyst-dependent ruffle formation remains unclear. Ruffles envelop bacteria, allowing subsequent internalization into Salmonella-containing vacuoles (SCVs). The SPI-1 T3SS effector SopD contributes to host cell invasion by promoting rapid severing (scission) of the plasma membrane (PM) invaginations at invasion sites, thereby generating SCVs. SopD encodes a GTPase activating protein (GAP) domain that promotes Guanosine-5'-triphosphate (GTP) hydrolysis by RAB10. By converting RAB10 to a GDP-bound state, SopD promotes recruitment of Dynamin-2 to drive the scission of the PM and also the removal of RAB10 from invasion sites. SobP, another SPI-1 T3SS effector, was shown to recruit RAB10 to invasion sites at the earliest stages (<10 min) of infection. Thus, we reasoned that the origin of RAB10 may provide insight into the membrane source for rSalmonella uses a type 3 secretion system to inject virulence proteins into host cells during infection. These proteins modulate host cell machinery to facilitate bacterial uptake into vacuoles, where they can replicate intracellularly. A key feature of Salmonella invasion is the formation of actin-rich protuberances (ruffles) on the host cell surface that aid in bacterial uptake. However, the membrane source for ruffle formation and how Salmonella regulates membrane mobilization within host cells remain unclear. This study shows that Salmonella exploits pre-existing membrane reservoirs for the generation of invasion ruffles. These reservoirs are tubular compartments associated with the plasma membrane (PM) and are formed through the activity of RAB10 GTPase. Under normal growth conditions, these reservoirs contribute to PM homeostasis and are preloaded with the exocyst subunit EXOC2. During Salmonella invasion, bacterial effectors SipC, SopE2, and SopB recruit exocyst subunits from membrane reservoirs and other cellular compartments, allowing exocyst complex assembly and membrane delivery required for bacterial uptake. The findings reveal an important role for RAB10 in the establishment of membrane reservoirs and the mechanisms by which Salmonella can exploit these compartments during host cell invasion. Salmonella enterica serovar Typhimurium (STm) is a gram-negative intracellular bacterial pathogen that is a major cause of foodborne gastroenteritis in humans. These bacteria can rapidly invade host cells using a type 3 secretion system (T3SS) encoded by Salmonella pathogenicity Island (SPI-1). SPI-1 T3SS effectors are known to promote the delivery of membrane to the invasion site via the exocyst complex, contributing to the formation of ruffles that envelop bacteria. However, the membrane source required for exocyst-dependent ruffle formation remains unclear. Ruffles envelop bacteria, allowing subsequent internalization into Salmonella-containing vacuoles (SCVs). The SPI-1 T3SS effector SopD contributes to host cell invasion by promoting rapid severing (scission) of the plasma membrane (PM) invaginations at invasion sites, thereby generating SCVs. SopD encodes a GTPase activating protein (GAP) domain that promotes Guanosine-5'-triphosphate (GTP) hydrolysis by RAB10. By converting RAB10 to a GDP-bound state, SopD promotes recruitment of Dynamin-2 to drive the scission of the PM and also the removal of RAB10 from invasion sites. SobP, another SPI-1 T3SS effector, was shown to recruit RAB10 to invasion sites at the earliest stages (<10 min) of infection. Thus, we reasoned that the origin of RAB10 may provide insight into the membrane source for r