Do I need a PhD in mathematics if my goal is to teach at the undergraduate level? My ultimate goal is to teach undergraduate level mathematics, that is, classes such as calculus and differential equations, as well as introductory proof-based courses like linear algebra, abstract algebra, and real and complex analysis. Why? I just love to teach people who are interested in learning math, and I have the strong belief (it's more of a certainty) that all interested mathematics students can appreciate and find the joy to learn any of these core classes if they receive the right approach. I am willing to teach like this patiently because I like it and I'm willing to devote to it. I feel very comfortable teaching math.

I am receiving a bachelor's degree in mathematics from UC Berkeley in May 2016. Needless to say, I like math a lot and I am excited to learn math at a higher level in grad school. 

My question is, given that my goal is to become a math educator and obtain a secured job, do I need to pursue a PhD in mathematics? 

I know that the whole idea in getting a PhD is to do original research, but to be honest, this is not the exciting part for me to go to grad school. This is merely secondary for me. I would even say it is tertiary since I am more enthusiastic about studying more math and being a graduate instructor. I know community colleges, liberal arts colleges, and even some universities hire lecturers (whose only job is to teach). Should I get into a master's program to achieve my dream job instead?
At least in the US, if you want to teach calculus, differential equations, and linear algebra, and are also willing to teach lower-level stuff (e.g., algebra stuff like quadratic equations and trigonometry) you can likely do that at a community college, which means you might not need a PhD. If you really want to teach abstract algebra and real analysis you probably could not do that at a community college, which means you'd probably need a PhD.