To be able to process the accounting in tunneling digitally, starting from the documentation of a tunneling cycle to the determination of the tunneling class, a creative solution approach is required. Using the open-source software tool TIMS (Tunneling Information Management System), an attempt is being made to redesign the current paper-based documentation and accounting methods in a new and digital way. In doing so, the standard-compliant handling of all individual steps up to invoicing is to be observed. In cooperation between IT engineers of the Vienna University of Technology and tunnel engi-neers of the Montanuniversität Leoben, TIMS is a new approach to represent the steps of documenting conventional tunnelling work as comprehensively as possible within one soft-ware solution. Documentation steps with later evaluation in the form of shift reports or exca-vation and support reports have already been implemented in TIMS. The topic of this thesis is to create a complete invoice from real data of an tunnel drive at the Zentrum am Berg. For this purpose, the still missing computation of the time-bound cost of the construction site was implemented in TIMS since, depending on the construction project, the time-bound cost can be approximately 15% to 20% of the total project cost in tunnel con-struction. An ÖNORM file automatically generated with TIMS was compared computationally to the original invoice documents of the Zentrum am Berg project for this purpose. With TIMS, it was possible to accelerate some processes in billing due to the automatic gen-eration of billing data. As a result of the direct data processing within the software because of unnecessary concurrently used Excel lists, possible sources of error are minimized or, at best, eliminated. The results shown in the paper demonstrate the potential of this software and should serve as a suggestion for future systems. To use software like TIMS under real circumstances, a new understanding of the "digital construction site" should be developed in the construction indus-try.