Unlike a T-shirt, a blazer has structure, so the fit is easy to judge once you know what to look for. These six checks apply to blazers and suit jackets.
The six-point check
- Shoulders. The shoulder seam should end where your shoulder ends. If it hangs past the edge, the jacket is too big, and shoulders are the hardest part to alter.
- Chest and closure. Button it. The front should lie flat. If the fabric pulls into an "X" shape around the button, it is too tight.
- Sleeve length. The sleeve should end around the wrist bone, showing roughly 1 to 1.5 cm (about half an inch) of shirt cuff.
- Jacket length. The hem should cover your seat, or end around the middle of your hand when your arms hang at your sides.
- Collar. It should sit against your neck and your shirt collar, without a gap at the back.
- Waist. There should be a slight taper. A little room is fine, but it should not billow.
What a tailor can usually fix
Sleeve length and the waist are usually simple to alter. Shoulders and collar are much harder, so choose the blazer that fits there and tailor the rest.
Sizing tips
- Blazers are often sized by chest in inches (such as 38R), where R, S and L stand for regular, short and long.
- Measure your chest at its fullest point. See how to measure yourself.
- Try it over the shirt you will usually wear.
- For an oversized look, the shoulder seam can drop slightly, as in our oversized hoodie guide.
Need a size recommendation?
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