The suit is the basic foundation of a professional wardrobe. You are likely to need this for office-based work, at least occasionally. There are also occasions such as weddings and funerals where you will need a formal suit. The requirement for suits has changed dramatically over the past 20 years. Up until the 2000s, almost all men would wear a suit (and usually a tie) to the office. Over time, habits from the tech industry have spilled over into all industries and this has resulted in much more casual dressing habits for work. This article will help you consider all the key points in choosing a formal suit.

However, depending on how formal your industry is, most men will need to have at least one suit for their work. If you are meeting clients / associates or senior members of staff, it makes sense to be able to pull off a very formal look. This conveys a more serious, professional attitude and will also make you feel more confident. The good thing these days is that it doesn’t take much effort to be the best-dressed person in your team / floor / company. Our guide will show you the basics and over time you will be able to develop your own personal style and tastes. 

There are many different types of suits which are discussed in other articles (casual suits, cotton suits) but for now we will concentrate on the basic set up for your formal suits. Shirts, ties and accessories will be also be addressed in further articles. 

What colour for professional suits?

The obvious factor to consider first is the colour. The two classic colours are navy and charcoal grey for business suits. These will both portray a sober, professional look. They are colours that mean that you don’t stand out. You don’t want a suit colour that will look out of place in a formal meeting, or look too different to the other people involved. The difference will come from other factors such as fit, quality, style, accessories etc. 

We would suggest navy as an essential colour for your formal suit wardrobe. A mid-navy will be best. Don’t go too dark (like a midnight navy) or too light (like an airforce blue). Mid-navy will be the most versatile colour, followed by a charcoal grey. It’s worth having both of them to start with so that you can alternate wearing them. It is important to try not to wear a suit on consecutive days so that you give the fibres some time to recover and for creases to fall out. This will also prolong the life of the suit. You will also want some variety in your outfits. 

What fabrics for formal suits?

What you’re looking for here is 100% wool. This gives the best trade off between price and performance. Wool is the best fabric for draping well (not rumpling or creasing) which will ensure a clean, professional look. After hanging the suit overnight, or steaming gently, any creases will fall out and it will be good to go again. 

There are cheaper suits that will incorporate synthetic materials such as polyester but it’s rarely worth wearing these. Within the wool category, there are also various different types but, as a wardrobe foundation, it’s worth going for 100% wool from a reputable brand. 

The next consideration is how the fabric is constructed which will affect the appearance and feel. There are variations that you will come across such as plain, twill, hopsack, houndstooth, glencheck, herringbone, and many more. The best option to start with is really a plain weave without risking any more unusual fabrics. Once you’ve got this solid foundation, it’s good to experiment with more patterns and weaves.

The weight of the suit is a key consideration. As a general rule, the heavier the fabric, the better it will look. The weight makes the material drape better and pulls out creases. What you select will depend partly on the climate in which you live and work. If you live in a hot, humid location, then you don’t want to go too heavy. Think of a weight of 310-320g as around average and vary it from there depending on how heavy you want to go. 

What style for formal suits?

A fairly standard style is best for a formal work suit. You don’t want any aspect of it to stand out or be too noticeable. Some of the factors to consider are:

• Shoulder roping: this is the amount of fabric that protrudes from the arm above the shoulder. It can give a very formal look by delineating the end of the shoulder. A jacket with no roping would look more like a shirt and makes it more casual. It’s better to have a bit of roping for a formal suit to differentiate it from its casual counterpart. 
• The lapel: the two main choices are notched or peak. For a single breasted work suit it is better to have a notched lapel. Peak lapels tend to be used more on double-breasted suits. It’s best to have a lapel width that is roughly halfway between the collar and shoulder seam. This is the classic menswear proportion. Fashions come and go here and the past couple of decades have seen much slimmer lapels be the mainstay of brands’ products. There is a move more towards wider lapels now but, as with most things in classic menswear we want to stay with the classic proportions and make only small adjustments.
• Single or double-breasted: this refers to whether there is more fabric at the front of the jacket which overlaps when it is buttoned. Double-breasted suits are a bit more old fashioned although they do have more of a ‘fashion’ element these days. It’s better to go for single-breasted to start with.
• Jacket buttons: the choice is between 2 and 3 buttons really. Go for 2.
• Pockets: for a standard formal suit, it’s going to be better to go for jetted, or flapped pockets, on the waist of the jacket and a welted pocket for the breast. You can also have a ticket pocket at the waist which is a smaller pocket above one of the waist pockets. This won’t make much difference to the formality but can be a nice addition.
• Jacket vents: the standard here is to go for two side vents. A single vent is more used for highly formal dinner jackets. 
• For the trousers, the key things are:
  • Do you want belt loops or side tabs / adjusters? It depends if you really want to wear a belt or not. Side tabs provide a cleaner look so I would go for these. Especially as it’s a nice way to differentiate smarter looks from more casual outfits.
  • Do you want pleats? These can make the trousers more comfortable by providing more room for when you sit down. A flat front gives a slightly cleaner look. 
  • Pockets: the most appropriate side pockets are slightly slanted. You definitely don’t want jeans type pockets on this suit. For hip pockets on the back, it doesn’t really make much difference whether you have one or (or none). You shouldn’t be using these anyway!

How should a formal suit fit?

Fit is really going to be the key differentiator between you and almost everyone else. By getting the details right, it will elevate your outfit way above the average. The vast majority of men don’t pay any attention to how their clothes fit. This won’t be immediately obvious to everyone but the overall picture will be subtly impressive if you focus on these key points of fit.

For the jacket, make sure that the shoulders fit properly i.e. the shoulder seam is roughly where your shoulder meets the top of your arm. The collar of the jacket should stay close to the shirt collar and there should be minimal gap (although some of this is inevitable when you move).

One aspect of the suit that won’t be immediately obvious is the armholes. For off-the-rack suits these are often made quite large so that they fit as many people as possible. This results in the jacket moving a lot when you move your arms. Ideally you want these armholes to be as small as possible. A bespoke jacket will do this for you but it’s harder to check on ready made garments. 

As regards the fit of the jacket through the body, we want to create a classic silhouette. This means enhancing the size of the shoulders relative to the waist. You can look up the golden ratio to see why. But bear in mind that you want to avoid the jacket being too tight. When the jacket is buttoned at the waist (the top button if you have two buttons) there should be minimal diagonal creases appearing. This can be altered by tailors if needed. 

Moving down the jacket, the sleeves should end roughly where there is a bony protrusion from the wrist. The idea is that the shirt worn underneath will show around a quarter of an inch. As shirt sleeves will also vary, it’s better to err on the side of a slightly shorter sleeve. Some shirt cuff on show under the jacket sleeve is an important part of the look. 

The bottom of the jacket should cover the seat but not be too long. A useful ‘rule of thumb’ is that when your arms are by your sides, the bottom of the jacket finishes somewhere between the joint and knuckle of the thumb.

The fit of the trousers should be in harmony with the jacket. If you have a roomy jacket fit then you’ll want a wider trouser fit. If you have a slim jacket fit, then you’ll want a slightly slimmer trouser fit. There is a bit of a trade off here with how the trousers fit at the seat. You want to minimise any horizontal creases when you are standing up. Whereas denim jeans cling to the body, the trousers for a formal suit should hang from the waistband as much as possible to create clean vertical drape of the fabric. See the article on trousers.

Finally, the length of the trouser should just touch the top of the shoe that you are most likely to wear with the suit. This may create a bit of a ‘break’ in the trouser fabric at the front. You can play around with this to get a fit that you like.

Key tips 

• Go for a mid navy or a charcoal grey suit to start with and then build out from there.
• Go for a 100% wool in a 300-350g weight. 
• Keep the fabric design fairly plain to start with – a plain weave or subtle herringbone / pinstripe.
• Don’t stray too far from standard proportions for things like lapel width, jacket length. 
• Fit is the most important thing. Remember that you can get a lot of things altered by a tailor for a reasonable price. 
• Don’t wear the suit too much (try to avoid consecutive days) and it will look much better and last longer.