<p>An internal thread is a widely used fastening element, important in many industries. Recently, a novel internal thread fabrication technique called drill thread milling has been introduced; it offers higher efficiency by simplifying the workflow into a single-step machining process. In this study, the cost–benefit analysis of DTM is compared to a multi-step process. A novel cost per part model and potential savings model that accommodates both single- and multi-step processes is proposed. The model integrates detailed contributing parameters such as tool movement, multiple tool change time, multiple tool life, tool cost, and uneven machining count for each tool. The model is applied to several use case scenarios that cover a wide range of possible application conditions. The results show that in many cases, DTM is still cheaper than the multi-step process even with higher tool cost, and the user can achieve significant cost savings when using DTM instead of the multi-step process. Furthermore, the cost per part model can potentially be used in other types of machining processes.</p>