True to size. I wish I didn't buy this jacket for farm/chicken chores. Seems too nice of a fit and jacket to wear while hauling dirt and mucking out the chicken coop or run but its stretchy enough to move and shovel in and my most comfortable chore coat. I bought true to size but still feels roomy enough to wear a hoodie under on very cold days and so far have been comfortable in 20-30F. Will put it to the test next week with multiple days near 0F
Only thing I can complain about is my chickens pecking at the shiny buttons... but that's on the chickens being busybodies and not against the super awesome jacket.