While the terms are often used interchangeably, the difference between swim trunks and swim shorts usually comes down to length, fit, lining, and intended use. Swim trunks are generally designed with swimming in mind, often featuring shorter lengths, quick-drying fabrics, elastic waistbands, and built-in lining. Swim shorts can be a broader category, ranging from classic swimwear to tailored styles designed to move easily from the beach to lunch, the pool to a yacht, or a resort afternoon to an evening by the water.
For a man building a holiday wardrobe, the choice is less about one being better than the other and more about how you plan to wear them. The right pair should feel comfortable in the water while fitting naturally into the rest of your resort wardrobe.
At a Glance: Swim Trunks vs Swim Shorts
The easiest way to understand the difference is to look at how each style is designed and where you are most likely to wear it.
Swim Trunks
- Fit: Usually more streamlined and designed with swimming in mind.
- Length: Most commonly available in shorter 5 to 7 inch inseams.
- Lining: Often features mesh or compression lining for added support and comfort in the water.
- Waistband: Typically designed with an elastic waistband and drawcord for a secure, adjustable fit.
- Best for: Swimming, pool days, beach days and traditional swimwear.
- Styling: Classic and practical, particularly suited to days spent in and around the water.
Swim Shorts
- Fit: Can range from relaxed to more tailored, depending on the style.
- Length: Often available in 7 to 10-inch lengths, including styles that sit above the knee.
- Lining: May be lined or unlined, depending on whether the design is intended primarily for swimming or broader resort wear.
- Waistband: Can feature an elastic waistband or a more tailored construction.
- Best for: Resort holidays, casual wear, beach lunches, pool clubs and hybrid beach-to-bar dressing.
- Styling: More lifestyle-led, making them easy to pair with linen shirts, polos, sandals and other resort pieces.
The terminology can vary between brands and regions, so there is some overlap. A pair marketed as swim shorts by one brand may be called swim trunks by another. What matters most is the construction, fit and intended use.
What Are Swim Trunks?
Swim trunks are a classic choice for men's swimwear. They are designed primarily for swimming, pool days, beach holidays and time spent in the water. The focus is usually on comfort, movement and quick-drying performance.
A typical pair of men's swim trunks has an elastic waistband with a drawcord, lightweight fabric and some form of internal lining. Mesh lining is common because it provides support while allowing water to drain quickly. Some styles use a compression liner instead, particularly when comfort and reduced friction are priorities during longer periods in the water.
Length is another defining characteristic. Five-inch swim trunks have become a popular choice for men who prefer a shorter, modern cut, while seven-inch swim trunks offer a little more coverage without feeling long. Both work particularly well for poolside and beach settings.
Swim trunks are also designed with movement in mind. Lightweight quick-dry fabrics mean they can go from the water to a towel and back again without feeling heavy for long periods.
What Are Swim Shorts?
Swim shorts are a broader term that can overlap with swim trunks, but they often include more lifestyle-led designs. Rather than being made exclusively for swimming, many swim shorts are designed to work as part of a complete resort wardrobe.
This is particularly useful when a holiday involves more than time in the water. A well-cut pair of swim shorts can work at the pool, on the beach, at a casual lunch or during an afternoon spent exploring a resort.
Tailored swim shorts are a good example. They can have a cleaner shape, considered pocket placement and a waistband that feels closer to a pair of casual shorts. Depending on the design, they may be lined or unlined.
For a resort wardrobe, this versatility matters. Pair swim shorts with a linen shirt and leather sandals for lunch, then head towards the pool without having to change your entire outfit.
What About Board Shorts?
Board shorts are another category of men's swimwear, but they are generally longer and more closely associated with active water sports.
Traditionally designed for surfing, board shorts typically sit around or below the knee and use a more secure waistband. Many have a rigid or fixed waistband rather than the elastic construction found on traditional swim trunks.
Board shorts are often unlined, allowing greater freedom of movement during surfing, wakeboarding and other active water sports. Their longer length also provides additional coverage when moving around on a board.
The difference between board shorts and swim trunks therefore comes down largely to length, construction and purpose. Swim trunks are usually shorter and designed for general swimming and poolside use, while board shorts are built with more active water sports in mind.
The Key Differences That Matter Most
Length
Length is one of the easiest ways to distinguish between different types of men's swimwear.
Five-inch swim trunks offer a shorter cut that works particularly well for swimming and modern poolside dressing. They allow plenty of freedom of movement and create a lighter feel around the legs.
Seven-inch styles offer a little more coverage while remaining firmly within the classic swimwear category. They are a practical choice if you want one pair that works across swimming, beach days and resort activities.
Longer swim shorts can extend above or towards the knee, offering a more casual appearance. Board shorts typically go further still, particularly when designed for surfing and other water sports.
There is no single correct length. Your choice should reflect how you plan to use the shorts, the amount of coverage you prefer and the overall style of your holiday wardrobe.
Lining and Comfort
Lining can make a noticeable difference when choosing swimwear.
Mesh lining is common in swim trunks because it provides support while allowing water to pass through. It is particularly useful for swimming and general poolside use.
Compression lining offers closer support and can help reduce friction during movement. This can be useful if you spend long periods walking, swimming or taking part in active beach activities.
Unlined swim shorts provide a different feel and can be particularly appealing when the design is intended to work beyond the water. They allow you to choose your preferred base layer and can make a pair of swim shorts feel closer to casual resort shorts.
When choosing between lined and unlined swimwear, think about how you will actually spend your day. If swimming is the main activity, built-in support can be useful. If your plans involve lunch, sightseeing and relaxed afternoons by the water, you may prefer a more versatile construction.
Fit and Styling
Fit is where swim trunks and swim shorts can start to feel quite different.
Traditional swim trunks tend to have a streamlined fit that keeps the fabric close to the body while allowing freedom of movement in the water. Swim shorts can offer a broader range of cuts, from streamlined designs to more tailored styles.
For a classic beach day, swim trunks work naturally with a simple T-shirt, sandals and sunglasses. For a resort setting, tailored swim shorts can be paired with an open linen shirt, loafers or leather sandals.
This is also why swim shorts have become an important part of modern resort dressing. The right pair does not have to stay at the pool. It can become part of the outfit.
Which Should You Choose?
Choose swim trunks if:
- You will be swimming regularly
- You want built-in support
- You prefer shorter inseams
- You want classic poolside styling
- You want lightweight, quick-drying swimwear
Choose swim shorts if:
- You want beach-to-bar versatility
- You prefer a tailored cut
- You plan to wear them beyond the water
- You want resort-ready styling
- You want one pair to work across different holiday settings
How to Choose the Right Pair for Your Holiday
The best pair of swim shorts depends on what your holiday actually looks like.
Start with activity. If your days are built around swimming, look for lightweight fabric, quick-drying construction and a supportive lining. If you are moving between the beach, lunch and the pool, a tailored pair can offer more versatility.
Next, consider inseam. Five-inch swim trunks are a strong choice if you prefer a shorter cut, while seven-inch styles provide a little more coverage. Longer styles can work well for a more traditional casual look.
Lining is equally important. Mesh lining offers classic swimwear support, compression lining can provide closer support, and unlined styles can work particularly well for hybrid beachwear.
Think about pockets too. Secure pockets are useful for resort days when you need somewhere for a room key or other small essentials. A comfortable waistband is just as important, particularly when you expect to wear your swim shorts for several hours.
Finally, consider how the pair works with the rest of your wardrobe. Swim shorts that complement linen shirts, lightweight cotton shirts and leather sliders can become much more useful than a pair reserved exclusively for the water.
For a beach holiday, the ideal pair is rarely just about swimming. It is about moving through the day comfortably.
Swim Shorts for the Modern Resort Wardrobe
The best resort wardrobes are built around pieces that can move with the day. Swim shorts are a natural part of that approach.
A tailored pair in navy, white, or a classic neutral can work with an open linen shirt during the afternoon and a simple polo for a more casual evening. A more distinctive print can bring personality to a poolside look without requiring much else.
This is where swim shorts differ from purely performance-focused swimwear. They can be part of the wider outfit rather than simply something you change into when you reach the water.
At Pier St. Barth, that connection between swimwear and resort dressing is central to the way we think about a summer wardrobe. The aim is to have pieces that belong naturally beside the sea, at the pool and everywhere in between.
Frequently Asked Questions
1. Are swim trunks and swim shorts the same?
Not always, although the terms are often used interchangeably. Swim trunks usually refer to swim-focused styles with shorter lengths, elastic waistbands and built-in lining. Swim shorts can describe a wider range of styles, including tailored and hybrid designs intended for both swimming and resort wear.
2. Can you wear swim shorts as regular shorts?
Yes, depending on the design. Tailored swim shorts with a clean finish, practical pockets and a considered fit can work as casual resort shorts. They are particularly useful for beach lunches, pool clubs and relaxed holidays where you want to keep your wardrobe simple.
3. What is the difference between swim trunks and board shorts?
Swim trunks are generally shorter and designed for swimming and general beach or pool use. Board shorts are usually longer, often unlined and designed for active water sports such as surfing and wakeboarding.
4. Do swim trunks need a lining?
They do not necessarily need one, but lining can provide additional support and comfort. Mesh lining is common in traditional swim trunks, while compression lining offers closer support. Unlined swimwear can also be comfortable, particularly for casual resort use.
5. What swim trunk length is most flattering?
The most flattering length depends on your preferred coverage and proportions. Five-inch swim trunks offer a shorter, modern cut, while seven-inch styles provide more coverage. The most important consideration is choosing a length that feels comfortable and works with how you plan to wear the shorts.
The Right Swimwear for Wherever Summer Takes You
Swim trunks and swim shorts may share much of the same territory, but they serve slightly different purposes. Swim trunks are a strong choice when swimming and traditional beachwear are the priority. Swim shorts offer a wider range of styling possibilities, particularly when you want your swimwear to work as part of a resort wardrobe. Board shorts sit further towards active water sports, with longer lengths and construction designed for movement.
Ultimately, the right pair is the one that suits your holiday. Look at the activities you have planned, the length you prefer, the support you want and how easily the shorts work with the rest of your wardrobe.
For a summer spent between the sea, the pool and the table, a well-chosen pair of swim shorts can be one of the most useful pieces you pack.
