The recycling of plastic waste has become increasingly important due to the negative impact of plastic on the environment. Additive manufacturing, also known as 3D printing, offers a promising solution for utilizing recycled plastics in the production of new parts. Due to increased demand and the production of polymers, recycling of plastic materials is highly sought nowadays. The thermo mechanical processes used to recycle these materials change their mechanical behavior. The current study focuses on the recycling of high-density polyethylene (HDPE), one of the most recycled materials in the world, to be recycled for use in additive manufacturing. Experimental testing and evaluation of the impact and tensile properties of fused filament fabrication (FFF) specimens made from virgin and recycled materials. This study reveals that the mechanical properties of the recycled HDPE polymer were generally improved over several recycling steps, making HDPE recycling a viable option for circular use. Moreover, repetitions two through five exhibited the best overall mechanical behavior, demonstrating that HDPE polymer recycling has a significant influence apart from the environmental one.