I'm 6'5" and finding well fitting shirts (or clothes in general) comes with the territory. It gets more challenging if you are a slender/athletic tall as bigger sizes that fit the torso and arm length tend to also widen out and have a lot of extra fabric if you don't have a stomach for it to wrap around. Here are some recommendations I have:
Figure out your neck and sleeve size, as these are commonly used to size shirts for men and can be useful depending on the button down you are looking for. Usually more oriented towards dress shirts. For reference, I am usually a 17 neck 35/36 sleeve.
Get a feel for different 'cuts' offered by brands (e.g. relaxed, slim, trim, etc.)
Some shirts will only be offered in S/M/L/XL sizes so focus on the L and XL.
Brands I have had success with:
Amazon Goodthreads (affordable, decent fit, can do Prime Wardrobe to try them on)
J Crew (sometimes cut is unflattering)
Banana Republic (have actually had decent luck here)
Rhone (just tried on some of their collared shirts, very comfortable and stretchy, but pricey. Material is thin so my chest hair was showing).
Ll Bean (often have tall sizes, but I find their shirts are cut more boxy and tend to billow out)
friendlyguy1989 t1_jclhzn4 wrote
Reply to Where do you guys get casual button-down shirts by UpvoteBeast
I'm 6'5" and finding well fitting shirts (or clothes in general) comes with the territory. It gets more challenging if you are a slender/athletic tall as bigger sizes that fit the torso and arm length tend to also widen out and have a lot of extra fabric if you don't have a stomach for it to wrap around. Here are some recommendations I have:
Good luck!