3D printing is advancing into the realm of production, both in terms of work-holding to assist in machining operations and custom end-use parts. While the value of a printer may not seem apparent at first, executing the calculations will tell a different story. In production and manufacturing, productivity is directly tied to revenue and performance. By offloading manufacturing and therefore costs from production machines or services to on-site rapid manufacturing machines, you can save money as calculated by a Return On Investment (ROI). The Return On Investment is an evaluation tool used to calculate the return you have achieved on an investment by percentage. This can apply to manufacturing technologies to help determine how much you can save by using something like a 3D printer. While the price of a production quality 3D printer may sound steep, it is the money you are saving by eliminating “routine” product manufacturing costs like work-holding, prototyping, and tooling costs that can make the printer worth the investment. In this white paper, we outline the steps you can take to calculate the ROI for a 3D printer. The Markforged Mark Two, a high-strength 3D printer that reinforces plastics with continuous fibers was used for these calculations. A similar procedure can be used for other 3D printing platforms.