I usually wear between a small and a medium depending on the cut of the shirt. I am 5’7”, weigh 130lbs, 34C, long waisted. This shirt is my new favorite! I am glad I gave it a second chance because the sizing is way off, but it is so worth it. I originally ordered a M, and it was extremely small! But the material was just what I was looking for so I ordered XL in my next order and they were perfect! The shirts are cut nice and long and going up in size gave me the fit I was looking for, perfect fit in the shoulders and chest and a little looser in the body. The fabric works great with HTV, and washed really well without any noticeable shrinkage. For reference, I have worn both Gap /Old Navy vintage and Target’s v-neck mossimo boyfriend tshirt for years as my go to casual vneck, but this is better than both in material and wear.