Bone tissues and bone marrow (BM) contain multiple tissue macrophages that support distinct functional niches: erythroblastic island macrophages support red blood cell production, haematopoietic stem cell (HSC) niche macrophages preserve a life-long pool of HSC, and osteal macrophages (osteomacs) promote bone development, health and regeneration. Bone and BM macrophages represent a virtually untapped common cellular target with demonstrated potential to simultaneously promote positive outcomes for both bone and BM health. To realise this opportunity, precision molecular profiling of the signatures underpinning macrophage distinct functional subsets is needed. Characterisation of bone and BM macrophage molecular profiles has been elusive, even when using sophisticated single cell approaches1. We exposed that cell events rationally gated as macrophages using flow cytometry analysis of bone-BM single cell suspensions were unrelated cells with membrane-encapsulated macrophage-remnants attached to their surface. Importantly, the macrophage-remnants contain high amounts of macrophage-derived proteins, intracellular reporter molecules and RNAs. The major implication is that the state of knowledge regarding bone and BM macrophage molecular profiles needs to be re-examined and validated. We next used in situ staining or imaging flow cytometry to interrogate whether reported expression of either other cell lineage specific markers on osteomacs or expression of myeloid/macrophage markers on other cells within BM accurately reflects intrinsic expression. Immunohistochemistry showed that CD110 (thrombopoietin receptor), reported to differentiate osteomacs from other BM macrophages2, is not expressed by osteomacs. Using Csf1r- or Siglec1-promoter driven reporter models combined with appropriate marker antibody panels, we show that reported HSC expression of the macrophage markers CD115 and VCAM1 is entirely derived from fragmented macrophage-remnants. In contrast, HSC expression of MHC class II was due to both HSC intrinsic and attached macrophage remnant expression. These data highlight that elevated scrutiny is required when applying ex vivo single cell analysis strategies to profile bone and BM cells.