Ice sheets supply iron (Fe), a bio-essential micronutrient, to the ocean. Yet, how glacier-fed fjords regulate this supply on annual timescales remains poorly constrained. Fjords may both remove dissolved Fe (dFe) through particle scavenging, and resupply dFe through reductive dissolution in sediments, making their net effect uncertain. By combining pelagic, benthic, atmospheric and freshwater observations, we construct comprehensive dFe budgets for three glacier-fed fjords in southeast Greenland, Sermilik, Sikuijivitteq, and Kangerlussuatsiaq. All fjords showed dFe enrichment relative to adjacent shelf waters, primarily associated with additions from subglacial discharge and submarine melt. However, export to the shelf was limited due to intense scavenging. In 2024, we estimate southeast Greenland fjords received new dFe inputs totaling 203 ± 21 Mg yr^-1 (excluding saline inflow), but ~66% of the gross dFe input was trapped within the fjords. The gross fjord dFe inputs were dominated by Atlantic inflow, runoff, and ice melt, with minor contributions from precipitation, dry deposition, and benthic efflux. The proportional importance of different contributions to net export is markedly different from gross fjord inputs. Ice melt represents the dominant contribution (70%), whereas export via glacially modified waters accounts for the remaining 30%. Greenland’s fjords therefore act as efficient filters, strongly attenuating dFe delivery to the ocean.

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