The shirt goes on tight as expected but needs to, to accomplish its goals of smoothing out the love handles and belly. Great for wearing under a dress shirt. As the day goes on you don't even notice the tightness of the shirt. I've used it a handful of times when needing to get dressed up and have got great results. I wear mostly x-large shirts but fit into a few large shirts. I would recommend going with your actual size shirt. If you think you can maybe fit into a smaller size regular shirt after then go smaller with the insta slim shirt for better results.