This work proposes an asymmetric SPDT transmit/receive (T/R) switch co-optimized with a low-noise amplifier (LNA) tailored to X-band operation and implemented in an 0.13 μm silicon-germanium (SiGe) BiCMOS technology. The switch achieves very high power handling capability in transmit mode, while maintaining low insertion loss, by utilizing an asymmetric topology. In receive mode, low noise is obtained by integrating a lumped-element matching network used simultaneously as a noise matching network for the LNA, as well as a lumped λ/4 transformer for the SPDT switch isolation. In transmit mode, the SPDT-LNA results in 1.1 dB minimum insertion loss, 26 dB isolation, and 26.9 dBm output P1dB at 10 GHz. In receive mode, the measured minimum noise figure (NF) is 1.9 dB with 15 dB gain at 10 GHz. To the authors' best knowledge, these results are the lowest NF and highest transmit output P1dB for any Si-based SPDT-LNA currently reported at X-band, and represents a significant step towards the realization of next-generation of Si-based high performance T/R modules.