In this paper, we derive a maximum velocity for anything with rest-mass from Heisenberg’s uncertainty principle. The maximum velocity formula we get is in line with the maximum velocity formula suggested by Haug in a series of papers. This supports the assertion that Haug’s maximum velocity formula is useful in considering the path forward in theoretical physics. In particular, it predicts that the Lorentz symmetry will break down at the Planck scale, and shows how and why this happens. Further, it shows that the maximum velocity for a Planck mass particle is zero. At first this may sound illogical, but it is a remarkable result that gives a new and important insight into this research domain. We also show that the common assumed speed limit of v < c for anything with rest-mass is likely incompatible with the assumption of a minimum length equal to the Planck length. So one either has to eliminate the idea of the Planck length as something special, or one has to modify the speed limit of matter slightly to obtain the formula we get from Heisenberg’s uncertainty principle.