How To Choose The Best Running Jacket

If you’ve ever set out for a run in the Cotswolds or braved the blustery streets of Manchester, you’ll know that British weather can be gloriously unpredictable. One minute it’s sunshine, the next it’s sideways rain or a biting wind that makes you question your life choices. That’s where a great running jacket comes in – your trusty shield against the elements, keeping you comfortable, dry, and motivated to keep moving, no matter what the forecast throws your way.

But with so many options, choosing the best running jacket can feel as daunting as a marathon finish line. Should you go waterproof or water-resistant? Lightweight or insulated? Hood or no hood? And what about all those technical terms – breathability, taped seams, hydrostatic head? It’s enough to make your head spin faster than your legs on race day...

Windproof running jackets are designed to shield you from cold gusts and blustery conditions, providing an essential barrier against the wind that can sap your body heat and make even mild days feel chilly. Their lightweight construction ensures you won’t feel weighed down, and their packability means you can easily stash them away when the weather calms, making them a smart choice for exposed routes, coastal runs, or breezy days on the trails. Many windproof jackets also offer a degree of water resistance, adding versatility for those unpredictable moments when a light shower rolls in, so you stay comfortable and protected without sacrificing breathability or freedom of movement.

Insulated running jackets are all about warmth, using synthetic or down insulation to trap heat and keep you cosy during frosty mornings, winter evenings, or whenever the temperature dips. These jackets are perfect for runners who feel the cold or enjoy slower-paced outings in chilly weather, as the insulation provides a comforting buffer against the elements. Despite their added warmth, well-designed insulated jackets remain breathable, allowing excess heat and moisture to escape so you don’t overheat, even if you pick up the pace or layer up underneath.

Packable running jackets are ultra-light and cleverly designed to fold into their own pocket or a compact pouch, making them a go-to choice for runners who value convenience and preparedness. While they aren’t built for heavy rain, they’re perfect for those unpredictable days when you want an emergency layer on hand—ready to deploy if the wind picks up or a shower starts. Their minimal bulk makes them easy to carry in a running belt or backpack, so they’re especially popular for race days, travel, or long runs where the weather can change quickly and you want to be ready for anything.

With so many technical terms out there, it’s easy to get lost in the jargon. Here’s what you actually need to know:

• Waterproof Rating → Measured in millimetres (mm), this tells you how much water a jacket can handle. 10,000mm+ is ideal for heavy rain.
• Breathability → Look for ratings in grams per square metre per 24 hours (g/m²/24hr). Higher numbers mean better moisture escape.
• Seams and Zips → Taped seams and waterproof zips stop water sneaking in.
• Reflectivity → Essential for safety in low light.

When shopping for a running jacket, you’ll often see terms like “10,000mm” or “20k waterproof” in the product description. These numbers aren’t just marketing jargon—they’re a direct measure of how well your jacket will stand up to wet weather. Here’s what you need to know to make sense of waterproof ratings and choose the right protection for your runs.

A jacket’s waterproof rating is determined by a test called the Hydrostatic Head (HH). In this test, a column of water is placed over a piece of fabric to see how high the water can go (measured in millimetres) before it starts to seep through. The higher the number, the more water pressure the fabric can withstand before leaking.

For example, a jacket with a 10,000mm rating can hold back a 10-metre column of water before any moisture penetrates the material. This gives you a clear, scientific way to compare how waterproof different jackets really are.

A high waterproof rating is important, but it’s not the only thing that keeps you dry. Look for these additional features:

• Taped seams → Prevent water from sneaking in at the stitching.
• Water-resistant zips → Stop leaks at the jacket’s most vulnerable points.
• Adjustable hoods and cuffs → Seal out rain and wind.
• Drop tails → Give extra coverage at the back for splashy conditions.

Remember, the more waterproof a fabric is, the less breathable it can be. For running, breathability is just as important—look for jackets that balance a high waterproof rating with good ventilation (such as underarm zips or mesh panels) and check the breathability rating if available (measured in g/m²/24hr).

Staying safe on your run is just as important as staying dry or comfortable—especially if you’re hitting the pavements early in the morning, after dark, or in low-light conditions. Reflectivity and visibility are key features that shouldn’t be overlooked when choosing a running jacket.

Many running routes, whether urban or rural, expose you to traffic, cyclists, or other hazards. A jacket with reflective elements ensures you’re visible from all angles, helping drivers and other runners spot you sooner. This is particularly vital during the shorter days of autumn and winter, or if you’re running in foggy or rainy conditions when visibility is naturally reduc

• Reflective strips or logos → These are often placed on the chest, arms, back, and zips to catch light from headlights or streetlamps.
• 360-degree reflectivity → Some jackets offer reflective details all around, making you visible from every direction.
• Bright or high-contrast colours → Fluorescent shades like neon yellow, orange, or pink boost your daytime visibility, while reflective details work best at night.
• Integrated lighting → Some high-end jackets even include built-in LED lights for maximum visibility.

Every runner is different, and your jacket should fit your routine as well as your body. Here’s how to choose based on your favourite runs:

For city runners, comfort and visibility are top priorities, given the stop-start nature of urban routes and the need to stay safe among traffic and pedestrians. A jacket with a waterproof rating between 5,000mm and 10,000mm is generally sufficient for city running, as you’re unlikely to be exposed to prolonged heavy rain, though those who regularly run in intense downpours may want to consider a rating closer to 15,000mm for added peace of mind. Materials such as polyester and nylon are ideal for city environments because they are lightweight, quick-drying, and durable, while a touch of elastane or spandex provides the stretch needed for unrestricted movement. Reflective details are essential for visibility in low light, and a streamlined fit ensures you look sharp and stay comfortable as you move through busy streets.

Trail runners require rugged protection and adaptability, as off-road routes often bring unpredictable weather, mud, and abrasive terrain. A waterproof rating of at least 10,000mm to 15,000mm is recommended to guard against moderate to heavy rain, while those tackling mountain or ultra-distance routes in wild weather should look for jackets rated at 20,000mm or higher. Advanced materials like GORE-TEX or Pertex membranes offer excellent waterproofing and breathability, which are crucial for long, strenuous efforts on the trails. Ripstop nylon adds durability against snags and scrapes, and hybrid constructions that combine waterproof panels with breathable fabrics in high-sweat areas help regulate temperature and keep you comfortable throughout your adventure.

Marathon trainers benefit most from lightweight versatility, as their focus is on logging miles in all conditions without being weighed down. A jacket with a waterproof rating between 5,000mm and 10,000mm usually provides enough protection, as most marathon training avoids the worst weather, but if rain is likely on race day, a jacket rated up to 15,000mm is a wise choice. Ultra-lightweight materials such as Pertex Shield or polyamide blends strike the right balance between weatherproofing and breathability, allowing you to pack the jacket away easily when it’s not needed. Minimal elastane ensures a comfortable fit without adding unnecessary bulk, and a simple, fuss-free design prevents chafing over long distances.

Cold weather runners need warmth without bulk, so a jacket with synthetic insulation and a waterproof rating between 5,000mm and 10,000mm is usually sufficient for snowy or lightly rainy conditions, though a higher rating may be necessary in freezing rain or slush. Synthetic insulation like PrimaLoft retains heat even when damp and dries quickly, while a nylon or polyester shell with a durable water-repellent coating keeps out wind and moisture. Merino wool blends are excellent as base or mid-layers beneath your jacket, providing natural warmth and moisture management without adding weight. Features such as body-mapped insulation and adjustable hems and cuffs help seal in warmth and keep cold air at bay.

For high-intensity and fast-paced runners, maximum breathability is essential, as these workouts generate significant heat and sweat. A jacket with a waterproof rating between 5,000mm and 8,000mm is usually sufficient, as you’re likely to avoid running in heavy rain and will benefit more from fabrics that allow heat and moisture to escape quickly. Materials like Pertex Shield or polyester blends are highly breathable and quick-drying, and mesh panels or vented designs under the arms or on the back further enhance airflow. A minimalist, athletic fit reduces weight and prevents flapping, ensuring you stay comfortable and focused during even the most demanding sessions.