Techniques for reassembly-free rewriting of out-of-order data packet payload are described herein. In one aspect of the invention, in response to packets received at a network access device from a first network node destined to a second network node, the packets are stored in a buffer within the network access device if the packets need to be modified before sending the packets to the second network node. The original our-of-order packets are dropped and do not reach the second network node. The payloads of the packets stored in the buffer are modified and thereafter, the modified packets with the modified payloads are sent to the second network node. Other methods and apparatuses are also described.