How to Buy a Button-Down Shirt Online: Chest, Sleeve and Fabric (What to Check)

A button-down shirt looks simple, but buying one online goes wrong in predictable ways: the chest balloons, the sleeves stop short of the wrist, the hem is too short to stay tucked, or the cotton turns out thinner or stiffer than the photo suggested. Most of those problems can be avoided before you order if you know which measurements to compare and how to read the fabric and fit notes. This guide covers chest, shoulder, sleeve and length, the common fabrics, and the return terms that matter.

Measure a shirt you already like

The most reliable sizing tool is a shirt that already fits you well. Button it, lay it flat on a table and measure:

• Chest: straight across from armpit seam to armpit seam, then double it. Many brands list the full circumference, so compare like with like.
• Shoulder: from one shoulder seam to the other across the back.
• Sleeve: brands measure this two ways, either from the center back of the neck to the cuff or from the shoulder seam to the cuff. Check which one the listing uses.
• Length: from the highest point of the shoulder, next to the collar, down to the hem at the back.

Write the numbers down and compare them with the garment measurements on the product page, not with your usual size letter. A medium at one brand can be two inches wider in the chest than a medium at another.

Understand the cut: slim, classic or relaxed

Brands describe fit with words such as slim, tailored, classic, relaxed or oversized, but those words only make sense next to a number. As a rough guide, a shirt with 4 to 6 inches more chest than your body measurement feels trim, 6 to 9 inches feels classic, and anything beyond that reads as relaxed. Women's shirts cut in a boyfriend or oversized style can measure 45 inches or more around the chest even in a small.

• Shoulder seam: on a fitted shirt it sits at the edge of your shoulder; on a relaxed or dropped-shoulder shirt it sits lower on the arm, which changes how long the sleeve needs to be.
• Model notes: use the model's height and size to judge proportions. A 6'1" model wearing a medium shows you a lot about length and drape.
• Size down or not: if a shirt is designed to be roomy, sizing down usually shortens the sleeves and body too, not just the chest.

Get sleeve length and body length right

Sleeves should reach the base of your thumb or the wrist bone with your arms relaxed, and still cover the wrist when you reach forward. If you are tall or have long arms, look for brands that list sleeve length for each size, or offer tall sizing. For body length, decide how you will wear the shirt. A tucked shirt needs enough length to stay in when you sit down; an untucked one should end somewhere around the middle of your zipper or seat. A curved shirttail hem is designed to be tucked, while a straight hem is usually meant to be worn out.

Read the fabric line carefully

Fabric changes how a shirt fits, wrinkles and wears over time:

• Poplin: smooth, light and crisp; good for warm weather and for wearing under a sweater, but it wrinkles easily.
• Oxford cloth: heavier with a visible basket weave; casual, durable and softer with every wash.
• Chambray: a light, denim-like weave that looks relaxed and hides wrinkles well.
• Flannel and corduroy: warmer and thicker, so they can feel snug if you plan to layer.
• Linen: airy and textured; wrinkles are part of the look.

Also look for "garment-washed" or "garment-dyed," which means the shirt was washed or dyed after sewing. These shirts are usually softer from the start, shrink less at home and can vary slightly in color. Small construction details, such as flat-felled or French seams and real shell buttons, are signs of better finishing and are often listed in the product details.

Check care and shrinkage

Untreated 100% cotton can shrink a little in a hot wash or dryer, mostly in length and sleeve. If the brand recommends washing cold and line drying, follow that until you know how the shirt behaves. A shirt that is a touch long at first is easier to live with than one that ends up too short after a few washes. Wool, cashmere and linen blends may need hand washing or dry cleaning, which adds to the real cost of the shirt.

Look at returns and exchanges before you pay

Because fit is uncertain, the return policy matters as much as the price. Before ordering, check:

• The window: some brands give 30 days or more, others as little as 14 or 21, sometimes counted from purchase rather than delivery.
• Fees: a flat return fee is common, and some brands waive it for exchanges.
• Final sale: discounted, monogrammed or personalized items often cannot be returned.
• International orders: some shops do not accept returns from outside their home country at all.
• Condition: try the shirt on with tags attached and do not wash it until you are sure.

For an example of a shirt-focused brand that lists chest, length and sleeve measurements on its product pages, along with a short return window and a return fee, see our Alex Mill review.

A quick checklist

• Measure the chest, shoulder, sleeve and length of a shirt that fits you
• Compare those numbers with the listed garment measurements, not just the size letter
• Check how the sleeve is measured, from the neck or from the shoulder
• Decide whether you will tuck the shirt and choose the length to match
• Read the fabric line: poplin, oxford, chambray, flannel or linen
• Look for garment-washed fabric and follow the care label to limit shrinkage
• Confirm the return window, any fee and the final-sale rules before ordering