The Ca2+ uptake properties of the sarcoplasmic reticulum (SR) were compared between type I and type II fibres of vastus lateralis muscle of young healthy adults. Individual mechanically‐skinned muscle fibres were exposed to solutions with the free [Ca2+] heavily buffered in the range pCa (=−log10[Ca2+]) 7.3 to 6.0 for set times and the amount of net SR Ca2+ accumulation determined from the force response elicited upon emptying the SR of all Ca2+. Western blotting was used to determine fibre type and the sarco(endo)plasmic reticulum Ca2+‐ATPase (SERCA) isoform present in every fibre examined. Type I fibres contained only SERCA2 and displayed half maximal Ca2+ uptake rate at ∼pCa 6.8, whereas type II fibres contained only SERCA1 and displayed half maximal Ca2+ uptake rate at ∼pCa 6.6. Maximal Ca2+ uptake rate was ∼0.18 and ∼0.21 mmol Ca2+ per litre fibre volume per second in type I and type II fibres respectively, in good accord with previously measured SR ATPase activity. Increasing free [Mg2+] from 1 to 3 mM had no significant effect on the net Ca2+ uptake rate at pCa 6.0, indicating that there was little or no calcium‐induced calcium release occurring through the Ca2+ release channels during uptake in either fibre type. Ca2+ leakage from the SR at pCa 8.5, which is thought to occur at least in part through the SERCA, was ∼2 fold lower in type II fibres than in type I fibres, and was little affected by the presence of ADP, in marked contrast to the larger SR Ca2+ leak observed in rat muscle fibres under the same conditions. The higher affinity of Ca2+ uptake in the type I human fibres can account for the higher relative level of SR Ca2+ loading observed in type I compared to type II fibres, and the SR Ca2+ leakage characteristics of the human fibres suggest that the SERCA are regulated differently than in rat and contribute comparatively less to resting metabolic rate. This article is protected by copyright. All rights reserved