How to Choose a Suit for a Teenager (Without it Becoming a Whole Ordeal)

When my eldest needed a suit for a family wedding last summer, I genuinely thought it would take an afternoon. Reader, it took three weekends, two meltdowns (one of which was mine) and a very stressful trip to Next where he stood in the changing room looking at me like I’d asked him to wear a costume. Choosing a suit for a teenager isn’t complicated in theory, but there are definitely a few things worth knowing before you start. The short answer? Go slim-fit, go navy or charcoal, don’t overspend, and brace yourself for at least some negotiation.

If you’ve got a school prom, a wedding, a leavers’ assembly, a bar mitzvah or any occasion on the horizon that requires your teenager to look Presentable with a capital P, this is everything I wish someone had told me first.

First, what’s the occasion? Because that changes everything

Before you look at a single suit, it’s worth thinking about what you actually need it for, because there’s a big difference between a suit for a prom and a suit for a formal wedding in a church.

For a school prom or leavers’ event, the dress code tends to be smart rather than strictly formal. There’s a lot more room for personality here and teenagers will often want something with a bit of edge, whether that’s a bold colour, an interesting texture or a more relaxed cut. This is where you’ve got the most flexibility.

For a wedding or christening, you’re usually looking at something more traditional and classic. Navy or charcoal, clean lines, proper shirt and tie. Nothing too fashion-forward if he’s going to be in family photos for the next thirty years.

For a job interview or sixth form open day, you want something that reads as polished without looking like he’s trying too hard. A well-fitted navy suit with a plain shirt and no tie often hits the right note.

Knowing the occasion upfront stops you buying the wrong thing entirely, which I absolutely did not learn the hard way. (I did. The wedding suit and the prom suit are two different suits, as it turned out.)

Fit is the thing that matters most

I cannot stress this enough. A cheap suit that fits well will always, always look better than an expensive suit that doesn’t. With teenagers this is especially tricky because their bodies are genuinely awkward shapes, often all arms and no shoulders, or broad across the chest but slim in the waist. Off-the-peg suits are cut for average adult proportions that simply don’t apply to most 13-17 year olds.

The most flattering cut for the vast majority of teenage boys is slim fit. It follows the body’s natural shape, it looks modern rather than old-fashioned, and it doesn’t swamp them the way a regular fit can. If you’ve ever seen a teenage boy in a suit that’s three sizes too big and hanging off his frame, you know exactly what I mean.

Here’s what good fit actually looks like:

• The jacket shoulder seam sits right at the edge of the shoulder, not drooping down his arm
• The jacket sleeves end at the wrist bone, with about a centimetre of shirt cuff visible
• The jacket buttons without pulling across the chest
• The trousers sit at the natural waist, not on the hips
• The trouser hem just grazes the top of the shoe, no pooling at the bottom

If something’s slightly off but otherwise close, alterations are your best friend. Most dry cleaners and tailors will take up trouser hems or take in a jacket for a very reasonable amount. If you’re buying from somewhere like Moss Bros or John Lewis, they’ll often do basic alterations in-store.

The growth spurt problem (it’s real and it’s annoying)

This is the one nobody really talks about in suit guides because most suit guides are not written by people who’ve watched a child grow three inches over one summer. Here’s the dilemma: teenagers grow, suits cost money, and there’s a genuine chance that by the time the event arrives, the suit you bought six months ago no longer fits.

My honest advice? Don’t buy too far in advance, especially if he’s mid-growth-spurt. Two to four weeks before the event is completely reasonable. And don’t spend a fortune on something he’ll wear once and grow out of.

If you do need to buy well in advance, some suits are made with extra fabric in the seams that can be let out by a tailor. It’s worth asking when you’re in the shop. Also, slim-fit suits in particular have very little room for adjustment, so for a fast-growing teenager, a slightly less fitted cut might actually make more practical sense even if it’s not quite as sharp.

The other option that nobody seems to mention: hire. Moss Bros has a hire service that’s brilliant for one-off formal occasions. If your son needs a proper morning suit for a summer wedding and you know he’ll never wear it again, hiring is genuinely sensible rather than spending several hundred pounds on something that ends up in the back of a wardrobe.

What colour to choose

This is probably the question I get asked most by friends who are going through the same process, and honestly the answer is almost always navy. Navy is smart, it’s versatile, it photographs well, it works for almost every occasion, and it doesn’t feel as heavy or funereal as black. It’s also much more forgiving with different shirt and tie combinations.

Charcoal grey is a close second. It’s a classic, it’s universally flattering, and it reads as properly formal without being as stark as black.

Black suits look sharp for very formal occasions or proms, but they’re actually quite a limited choice day-to-day, and they can look a bit much on younger faces in certain settings.

If the prom or event has a more relaxed or fashion-forward dress code, a mid-grey, a stone/sand colour, or even a subtle check or texture can look brilliant. This is where your teenager’s input is actually helpful rather than a hindrance, because he’ll know what his friends are wearing and what the vibe is. My eldest went for a grey check suit for his prom and it looked genuinely brilliant.

One thing to avoid: very cheap suits in deep burgundy, royal blue or bright green. They look tempting online and in photos, but in person the fabric quality tends to be very obvious and they can look quite costume-y. If you want a fashion colour, go for something in a subtle tone and from a decent brand rather than the cheapest option on ASOS.

Where to actually buy a suit for a teenager in the UK

This is where UK-specific advice is actually useful, because most of the suit guides floating around online are very American and the brands they recommend either don’t exist here or are wildly overpriced for what you need.

Here’s where I’d genuinely look:

Next is my first stop for budget-to-mid range. Their slim-fit suits for older teenagers are good quality for the price, the sizing runs up into adults so you’ve got a good range, and you can often pick up a full suit for £60-£80. The fit is generally really solid.

Marks and Spencer is excellent for quality and has a great range of suit separates, which is handy if your teenager is an unusual shape. You can buy a jacket in one size and trousers in another, which is something high street brands often don’t allow. Slightly pricier but the quality is noticeably better.

Moss Bros is brilliant for older teenagers who are closer to adult sizing. Good quality, proper suit fit, and they do tailoring adjustments in-store. Worth checking the sale too.

ASOS has a huge range and suits plenty of budgets, but sizing can be inconsistent and returns can be faffy. Best for teenagers who know their measurements well and have been fitted before.

Zara does genuinely stylish slim-fit suits that look much more expensive than they are. Great for proms or fashion-forward occasions. Their suit trousers in particular are brilliant.

John Lewis for quality and excellent customer service. Not the cheapest, but if you’re buying something that needs to last a season or two and look properly sharp, it’s worth the investment. They also carry some great brands for older teens.

For budget situations, don’t completely overlook charity shops and preloved. For a one-off event, a well-looked-after second-hand suit in good condition is perfectly reasonable, and you can often find quite good quality pieces. 

The shirt and tie situation

A suit without the right shirt and tie can look completely unfinished, and this is where a lot of people get caught out. Here’s the easiest approach:

Start with a plain white or pale blue shirt. It works with everything, it photographs beautifully, and it doesn’t compete with anything else in the outfit. If your teenager wants to express some personality, the tie is the better place to do it rather than the shirt.

For ties, a plain or subtly patterned tie in a colour that picks up something in the suit always works well. Navy suit, burgundy tie, for example. Or charcoal suit, forest green tie. It’s a classic combination formula that genuinely doesn’t fail. If he hates ties, a well-fitted suit with an open collar and a good shirt can actually look quite modern and intentional rather than like he forgot the tie.

Pocket squares are optional but they do add a nice finishing touch, especially for proms or weddings. They don’t need to match the tie exactly; in fact a bit of a contrast often looks more sophisticated than a matchy-matchy set.

The shoes matter more than you think

This is the bit that parents often sort last-minute and it genuinely shows. Trainers with a suit can work for certain very casual or fashion-forward occasions, but for a wedding or formal event, proper shoes make the whole outfit look intentional and pulled-together.

Classic black or dark brown Oxford or Derby shoes are the safe, reliable choice. They don’t need to be expensive, just well-maintained. If he doesn’t have any, a decent pair from NEXT or Clarks will do the job absolutely fine. 

The one thing I’d say: sort the shoes before the suit trousers are hemmed, if you’re getting them altered. The break of the trouser leg looks different depending on the heel height of the shoe, so it’s worth trying everything on together before you commit to a hem length.

Getting a teenager to actually engage with the process

Okay, real talk. This might be the most useful section of the whole post.

Some teenagers are genuinely fine with suit shopping. They try things on, they give useful feedback, it takes an hour and you both come home happy. My children are not those teenagers. If yours is similarly enthusiastic about shopping, wonderful. If not, here’s what I’ve learnt.

Give him some genuine choice. Let him decide on the colour if you can. Let him choose between two or three options rather than presenting one thing and asking for approval. Teenagers dig their heels in when they feel like something’s being done to them rather than with them, and honestly that’s fair enough.

Don’t take him shopping tired or hungry. This sounds obvious but I cannot tell you how many suit shopping trips I’ve attempted after school on a rainy Tuesday and had to abandon.

Keep it short. One or two shops, clear objective, done. If you haven’t found it in two hours, go home, regroup, and go back another day. Extending a difficult shopping trip never, ever improves it.

And genuinely, show him pictures of men in well-fitted suits who he might respect or admire. Athletes in formal wear, musicians, actors. Not because he needs to look like them, but because sometimes a reference point helps a teenager understand what “smart and well-fitted” actually looks like in practice, rather than imagining he’s going to end up looking like his grandad at a funeral.

How much should you actually spend?

This depends on how many times he’s likely to wear it. If it’s a one-off event and he’s mid-growth-spurt, spend as little as you can get away with while still getting a decent fit. £60-£100 from Next or similar is absolutely fine.

If he’s 16 or 17 and closer to his adult size, and you’re thinking this could do for interviews, sixth form events and maybe one or two more formal occasions, it’s worth spending a bit more for something that holds up. £150-£250 from somewhere like Moss Bros, John Lewis or M&S will get you genuinely good quality that looks sharp and lasts.

Buying a complete suit set (jacket, trousers, sometimes a waistcoat) tends to be better value than buying separates unless you specifically need the flexibility of different sizes for top and bottom.

Frequently asked questions

What’s the best suit colour for a teenage boy?

Navy is almost always the best starting point. It’s versatile, smart, and works for everything from school proms to weddings. Charcoal grey is a great alternative if you want something a bit more formal or traditional. Black is fine for very formal or evening events but is quite limiting for other occasions.

Should I buy a slim-fit or regular-fit suit for a teenager?

Slim-fit is generally much more flattering on teenage bodies. Regular-fit suits can look baggy and shapeless on slimmer frames, which is most teenagers. That said, if your teenager is broader or more solidly built, a regular fit might actually be more comfortable and look more proportionate. Try both if you’re not sure.

Where’s the best place to buy a suit for a teenager in the UK?

For good quality at a reasonable price, Next and M&S are both excellent. Moss Bros is brilliant if he’s closer to adult sizing. Zara is great for a more fashion-forward look, especially for proms. John Lewis is worth it if you want to spend a bit more for quality and good in-store service.

How do I know if a suit fits properly?

The jacket shoulder seam should sit right at the edge of the shoulder without drooping. The sleeves should end at the wrist with a sliver of shirt cuff showing. The jacket should button without pulling across the chest. Trousers should sit at the natural waist and the hem should just brush the top of the shoe. If the shoulders fit, most other things can be adjusted by a tailor.

Is it worth getting a teenage suit altered?

Yes, for the jacket shoulders especially, but alterations for a cheaper suit aren’t always worth it if they’d cost more than the suit. Trouser hems are cheap and easy to alter and make a big difference to the overall look. If you’re buying somewhere like Moss Bros or John Lewis, ask about their in-store alteration service.

The short version, for those who’ve scrolled to the bottom

Choosing a suit for a teenager doesn’t have to be a big production, even though it sometimes turns into one. Go slim-fit, go navy or charcoal, buy from somewhere with a decent return policy, don’t spend a fortune if he’s going to grow out of it, and sort the shoes before you get the trousers hemmed. Give your teenager some genuine input into the process and it’ll go much more smoothly than if you turn up with a firm idea of what he’s going to wear.

We’ve done this twice now with two teens and I’ve learnt something new each time. The main one being: always, always have a snack in your bag before you go.

 

See more parenting posts here and more teenager posts here!