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The propagation of bound and free infragravity wave energy under short-wave breaking conditions induced by a longshore bar is investigated through field observations. Near-bottom pressure records deployed in a cross-shore array at S. Jacinto barred beach (Portugal) were analysed. In these observations, short-wave breaking induced by the longshore bar occurred mainly in intermediate water depths. The ratio between bound and total (bound plus free) infragravity wave energy was estimated with the methodology of Herbers et al. (1994). This ratio had a maximum value of 0.6 at the breaking onset, which is consistent with values presented elsewhere. A decrease of the bound infragravity wave energy was observed after short-wave breaking near the bar crest. This is in part due to nonlinear energy transfers from infragravity to short-wave frequencies as detected on the imaginary part of the bispectrum, in a weakly dispersive Boussinesq approximation. The other part is due to the process of release/transform bound into free infragravity wave energy that was assessed with a simplified energy balance equation. A conceptual model for the exchange of bound infragravity wave energy during short-wave breaking in intermediate water depths is proposed. This conceptual model involves both the kh and the ga/C 2 generalized nonlinearity parameter. • Field observations of bound infragravity wave energy during breaking and non-breaking short-wave conditions over a bar. • Nonlinear energy transfers from infragravity to short-wave frequencies increase with generalized nonlinearity parameter ga/C 2 . • A conceptual model for bound infragravity wave energy during short-wave breaking in intermediate water depths is proposed. [ABSTRACT FROM AUTHOR]