Embodiments are generally directed to message authentication code (MAC) based compression and decompression. An embodiment of an apparatus includes one or processors to process data; and a computer memory; wherein the one or more processors are to perform compression of a fixed transmission or storage unit, the transmission or storage unit including multiple slots, the compression of the transmission or storage unit including the one or more processors to calculate a MAC for data in the transmission or storage unit, determine whether a special value is present in any slot of the transmission or storage unit, and upon determining that the special value is present in a respective slot of the transmission or storage unit, remove the special value from the transmission or storage unit, shift remaining data of the transmission or storage unit to provide room in a first slot the transmission or storage unit, and insert the MAC in the first slot to generate a compressed transmission or storage unit.