Over the past decades, wear phenomena in engineering applications have been extensively studied and simulated using numerical methods. Classically, wear modeling has relied heavily on Archard’s wear law. Despite its widespread use, Archard’s model implicit presumes that detached wear particles are instantaneously removed from the contact interface, neglecting their potential influence on subsequent contact conditions. In practice, however, purely two-body contact is rare in tribological systems. Wear debris often remains within the interface, forming a third-body that modifies load transmission, frictional response, and wear evolution. For example, this behaviour is significant in fretting contacts, where limited relative motion promotes debris accumulation [1], and in polymer systems, where compacted wear particles can form protective layers [2], known as transfer films. Although it is nearly ubiquitous, the third-body effect has received relatively little attention in computational wear modeling, which motivates the present work. This contribution presents a novel finite element computational strategy for simulating wear in mechanical contacts, explicitly considering the role of third-body particles. We depart from a macroscopic continuum-based approach that accounts for the presence of third-body particles, their formation, accumulation, and loss within the contact interface. A dual mortar-type discretisation is employed to ensure a robust enforcement of contact and frictional constraints under evolving interface conditions. Wear and debris are described through state-variable fields [3], allowing their influence on contact mechanics, friction, and wear rates to be captured in a consistent manner. To represent debris redistribution, a dedicated transport strategy is introduced to model the handling of state variables within the contact interface. The proposed framework is validated through numerical examples, demonstrating its qualitative predictive capabilities and potential to guide the design of more durable tribological systems. [1] S. Fouvry et al., Wear, 257, 916–929, 2004, doi:10.1016/j.wear.2004.05.011. [2] S. Bahadur, Wear, 245, 92–99, 2000, doi:10.1016/S0043-1648(00)00469-5. [3] N. Strömberg et al., Int. J. Solids Struct., 33, 1817–1836, 1996, doi:10.1016/0020-7683(95)00140-9.