The present embodiments support both tunneling and offload functionality for tunneled packet having a tunnel header, the tunnel header encapsulating a packet, the packet having a packet header and a payload. When a tunneled packet is received at a network device, an offset value for the packet header is determined by comparing the tunnel header to a plurality of entries stored at a data structure maintained by the network device. The offset value is used for pre-processing the packet, and an offload module of the network device performs an offload function.