The Cretaceous-Paleogene (K-Pg) boundary represents the most recent mass extinction in Earth history. Although it is widely accepted that a bolide impact in North America caused the extinction, many questions persist about how this impact affected Earth's climate and environment. Here we explore changes in organic matter inputs across the K-Pg in an impact-distal section in New Zealand (mid-Waipara River section, North Canterbury, New Zealand). The section is 21.2 m thick, including 1.2 m of uppermost Cretaceous and 20 m of lower Paleocene sediment, the latter spanning ~1 Myr, albeit interrupted by at least one major unconformity. We examine the abundance and distribution of n-alkanes and n-alkanoic acids (mixed sources), acyclic isoprenoids (pristane and phytane), steranes (eukaryotes), hopanes and hopanoic acids (bacteria) and GDGTs (glycerol dialkyl glycerol tetraether lipids) to explore changes in the relative contribution of marine vs terrestrial sources. Minimal differences in the biomarker assemblages between sediments below and above the K-Pg boundary suggest a rapid recovery of the non-fossilizing phytoplankton community, similar to that observed in other distal settings. However, the organic matter source became variable immediately after the impact event. Variations in the concentrations and distribution of the high-molecular-weight n-alkanes and n-alkanoic acids, terrestrial-aquatic ratios, and GDGT branched to isoprenoidal tetraether indices indicate an increase in the absolute and proportional abundance of terrestrial soil- and plant-derived organic matter just after the impact event. This co-occurs with an apparently transient decline in marine productivity, indicated by a decrease in concentrations of low-molecular-weight n-alkanoic acids, concentrations of pristane + phytane (of putative algal chlorophyll origin), and sterane/hopane ratios. This suggests that the bolide did affect the mid-Waipara biomarker-producing bacterial and algal assemblages, distinct from what has been observed at other distal sites. However, it remains unclear if this was a direct consequence of the impact or the wider post-impact reorganisation of environment and oceanography as has been previously observed in this region.