As both the IGES/IGS and STP/STEP are fairly common CAD formats used for exchange purposes, so it should be fairly easy to find a program that can convert one to another.
Convert IGES 3D exchange format to ISO-10303 STEP product data.
We found 17 software records in the database related to .iges to .step file format conversion.
Microsoft Windows software - convert iges to step on Windows
A 2D and 3D CAD construction software
Convert from iges file format
The tables with software actions are a good pointer for what a certain program does with various file types and often may give users a good hint how to perform certain file conversion, for example the above-mentioned iges to step. However, it is not perfect and sometimes can show results which are not really usable because of how certain programs work with files and the possible conversion is thus actually not possible at all.
Autodesk Inventor is modeling application used to create 3D digital prototypes.
A 3D model converter
A 3D modelling software
Leading 2D and 3D CAD development software from Autodesk
A CAD converter with huge format support
A widely-used 3D animation application from Autodesk
A set of 3D modeling tools
Apple macOS / Mac OS X software - convert iges to step on OS X
Mac version of popular Autodesk AutoCAD software
Multiplatform software - convert iges to step on any platform
An open source multiplatform 3D CAD/MCAD/CAx/CAE/PLM modeler