Quantum communication offers many applications, with teleportation and superdense coding being two of the most fundamental. In these protocols, preshared entanglement enables either the faithful transfer of quantum states or the transmission of more information than is possible classically. However, channel losses degrade the shared states, reducing teleportation fidelity and the information advantage in superdense coding. Here, we investigate how to mitigate these effects by optimizing the measurements applied by the communicating parties. We formulate the problem as an optimization over general positive operator-valued measures (POVMs) and compare the results with physically realizable noiseless attenuation (NA) and noiseless linear amplification (NLA) circuits. For teleportation, NLA or NA and optimized POVMs improve the average fidelity by up to $78\%$ while maintaining feasible success probabilities. For superdense coding, they enhance the quantum advantage over the classical channel capacity by more than $100\%$ in some regimes and shift the break-even point, thereby extending the tolerable range of losses. Notably, the optimal POVMs effectively reduce to NA or NLA, showing that simple, experimentally accessible operations already capture the essential performance gains.

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• Quantum communication
• Quantum communication, protocols & technology
• Quantum protocols
• Quantum state transfer