The impetus of this experimental investigation is to analyze the laminar forced convection of water-based nanofluid (NF) including Fe3O4 nanoparticles inside a twisted tube. The impacts of NF concentration (0% < $$ \varphi $$ < 2%), Reynolds number (500 < $$ {\text{Re}} $$ < 2000) and twist pitch (10–100 mm) on the average Nusselt number ( $$ \overline{\text{Nu}} $$ ), friction factor, and overall hydrothermal performance indicator are assessed, and the results are compared with those of the plain tube. It was found that the $$ \overline{\text{Nu}} $$ of NF rises with boosting $$ \varphi $$ and $$ {\text{Re}} $$ , while it declines with boosting twist pitch. In addition, it was found that the rise of $$ \varphi $$ causes a rise in the friction factor, while it diminishes with the rise of $$ {\text{Re}} $$ and twist pitch. Moreover, the results depicted that the overall hydrothermal performance of NF in the twisted tube is superior to that of the water in the plain tube. The best overall hydrothermal performance of the NF occurred at $$ \varphi $$ = 2%, $$ {\text{Re}} $$ = 2000 and twist pitch = 10 mm.