Some events call for traditional eveningwear, others for elegant variation. Here’s how to know which is which.

The first rule of black tie is: you’ve got to dress up. If the invitation says “black tie optional”, it’s really not. It’s what the hosts want you to wear, they’re just trying not to be autocratic about it.

The second rule is: don’t rent a tuxedo. For starters, it ends up being a false economy. If you buy one it will last for a decade or more, so even if you only wear it a handful of times a year, you’ll end up getting some good wear out of it. But also consider that the occasions when you are required to wear black tie are invariably special ones when photographs are taken and you want to look your best. What you don’t want to be wearing is an ill-fitting cheap suit that gives off the heady aroma of previous renters as the dancing begins.

What about the other rules? Do you stick to them religiously or fiddle them rebelliously? Either way, you first need to know what they are. By way of explanation, our editors have assembled five different interpretations of “black tie” that run the full length of the red carpet, whether you’re going to a gala dinner or a raucous rock ’n’ roll party.

Let’s start with the foundational principles of traditional black tie and build from there. A black tuxedo is rarely wrong, which is why we currently offer a selection of them on the site. If you were only ever going to buy one tux and wanted a one-style-fits-all that will last for years, then this is the timeless classic that has been doing the job for decades. It will fit the bill from everything to a high-school prom to a black-tie wedding or a gala dinner.

Do not think a regular black suit will suffice – it won’t. What you’re looking for is a peak or shawl lapel (never notch) with grosgrain or satin facing which matches with the stripe down the outer seam of the trousers. Whether you choose peak or shawl lapel comes down to personal preference but also your proportions. Consider your frame and even the size of your head: a slimmer, smaller man suits a slimmer lapel, whereas a broader person will be better off with a wider lapel. And while we’re on the subject, make sure the proportions of your lapel, shirt collar and bow tie all more or less match up.

The jacket should have one button, maximum two, of which you would only ever do up the top one. It should be fastened when standing and unfastened when sitting down. Tuxedo trousers should not have belt loops for they must never be worn with a belt – get them altered to fit if necessary. They should finish on the shoe which is usually a highly polished black leather. And make sure your socks are black and calf length so there is no distracting visual disconnect at the ankle – you should not be exposing any skin, even when seated. Wear an elegant slim-line dress watch, ideally on a black leather strap, that will sit flush against your wrist and not interfere with any cufflinks you might be wearing. Ideally you want to show between half-an-inch and an inch of shirt cuff.

There is one main caveat to the above, which sounds rather elitist: a black tuxedo is traditionally also worn by waiting staff so, in Europe especially, midnight blue might be preferable. Unless you enjoy having people ask you to top up their champagne all evening. Alternatively, you could set yourself apart by adding some individual flourish to an otherwise conventional get-up: for example, wearing dress studs instead of shirt buttons as demonstrated here, and perhaps popping a pocket square in your breast pocket.

Snobbery aside, the key advantage of a midnight blue tuxedo jacket (such as this from our in-house tailoring line Kingsman) is that it looks more flattering in flash photography, and often actually shows up darker than black under artificial light. Such a jacket would usually be worn with its matching midnight blue trousers. However, because the lapel is black, it can also be paired with separate black tuxedo trousers – ideally the lapels and seam stripe should agree for some through-line consistency (grosgrain with grosgrain; satin with satin). Again, one would usually wear shiny black shoes with such an ensemble, but here we’re controversially pushing the boundaries for the purposes of demonstration with a pair of burnished burgundy lace-ups. Note how even though the dark palette very much denotes eveningwear, the differing tones serve to bring out the respective colours which breaks up the monochrome monotony.

A few thoughts on bow ties. Over the past decade it became acceptable in all but the most formal and traditional of settings to wear a plain black necktie in place of a bow tie. However, the pendulum has now swung back in favour of a dickie-bow. Resist any temptation to try any colour of bow tie other than black or midnight blue. Just: no. However, you can vary the texture, whether velvet or grosgrain or silk. An important life skill: learn how to tie a real one. And don’t leave it until the last moment before you panic-Google how to do it. Fiddly knots become fiddlier still when you’re against the clock. As the guys in the YouTube videos smugly demonstrate, tying a proper bow tie is not that difficult, and it looks so suave worn undone Bond-style. As a bit of a cheat – you could secrete a self-tie bow tie in your inner breast pocket and nip to the bathroom to do the ol’ switcheroo at the cognac end of the night. We won’t tell.

A white dinner jacket (actually ivory or cream, usually) is a particularly strong look if attending a formal event in a warm climate – say, a wedding abroad. Even more so if you are the groom and you wish to co-ordinate with the bride but differentiate yourself from the guests. Such a jacket is generally considered a little dressier and is usually made of a lighter material than a black tuxedo. It is, of course, a high-risk choice: beware of red wine spillages.

Wear the jacket with plain black tuxedo trousers. In terms of footwear, velvet or suede dress slippers are a dapper alternative to patent leather Oxfords, although they are traditionally reserved for “at home” invitations, so consider the practicalities of wearing them outside. Here, we have chosen a tassled Gucci loafer in black leather which is like an outdoor slipper. Avoid brogues or Derbies – they are not formal enough for eveningwear.

The crisp whiteness of your shirt will enhance the ivory hue of the jacket. When wearing a bow tie, which leaves so much of the chest exposed, a regular dress shirt won’t do – it needs to be an eveningwear shirt with a marcela bib (that textured fabric like the dimples of a golf ball) or a pleated front. Ruffles are only for the brave. Keep your cufflinks simple – gold, silver, mother of pearl and onyx are your options. Your metals should agree with any watch and/or shirt studs you might be wearing. Please, don’t get us started on novelty cufflinks, or novelty anything, in fact.

Velvet jackets are an elegant and versatile variation on a tuxedo, especially during the darker, colder months of winter. Mr Tom Ford is a modern-day style icon when it comes to eveningwear and he has made velvet a louche, late-night signature. This deep burgundy jacket is one of his. Midnight blue, bottle green or black will also work. And of course the Kingsman orange velvet number if you have the gala balls to pull it off. But consider the occasion: you would not want to out-dress the birthday boy at his 40th or 50th. But if you are said birthday boy, go for it.

Such a velvet jacket would look very elegant with a simple bow tie and white shirt, of course, but if that feels too stiff, a rollneck sweater is a rakish alternative. Since you’ll be wearing it all night, make sure it’s not going to get hot and itchy. This option from Loro Piana, in black baby cashmere, is so soft it won’t cause any irritation around the neck.

A velvet jacket opens up more possibilities in terms of footwear. Texture-wise, suede dovetails very nicely. Black would be the norm but for variation we have chosen a Chelsea boot in olive green-brown which works with the deep lustre of the burgundy jacket.

There is a sliding scale of formality when it comes to eveningwear. Some occasions and venues (such as gentlemen’s clubs with severe dress codes) are so rigid and posh that it is advisable to play it straight and abide by the hard and fast rules of convention. At the other end of the spectrum? Well, pretty much anything goes.

You may occasionally hear the terms “Hollywood black tie” or “creative black tie”, which are essentially a licence to experiment – sometimes too much licence for too much experimentation. But, however loose your interpretation of black tie, remember the golden rule: make an effort. Here we see a slim-line satin-trimmed black tuxedo from Saint Laurent given a distinctly rebellious twist when styled with an unbuttoned print shirt worn with a pendant. Think Mr Harry Styles on the red carpet. The chunky bracelet is echoed in the chain-trimmed leather loafers from Tom Ford.

Shop all black-tie wear here