Low bit-rate speech coders are important in many critical communication systems such as military, police, fire departments, homeland security and other first responders. The need for elimination, reduction of the redundancy or irrelevant information from the analog signals gave birth to an area of speech coding. The main goal of speech coding is to represent speech with the minimum number of bits by maintaining its intelligibility and perceptual quality. In today’s wireless communication system there are many factors to be considered but the most constraint is the bandwidth and power. Accommodating more users within a limited bandwidth is a big challenge in the mobile communication system. Still the manufactures and service providers are in search for the low bit-rate speech coders that deliver toll quality speech. The objective of this paper is to compare the commonly used algorithms in wireless communication systems such as LPC, PCM, ADPCM, CELP and VSELP.