A modular strapping head assembly includes a body, a weld head assembly, a drive motor configured to control the weld head assembly to grip and seal strapping material, a transformer assembly, and a single power interface configured to direct power from a source to the drive motor and the transformer assembly. The transformer assembly is configured to supply current to the weld head assembly and the weld head assembly is configured to seal a lagging end of the strapping material and a leading end of the strapping material together. Each of the transformer assembly, the drive motor, the weld head assembly, and the power interface are mounted to the body and removable from the strapping machine as an integral unit.