Quick answer: Most ultras require broadly the same mandatory kit: a genuinely waterproof jacket with taped seams, a spare base layer, hat and gloves, a foil blanket or survival bag, a whistle, a charged phone, a headtorch with backup for anything running into darkness, a cup, minimum water capacity, emergency food, basic first aid items, and the course loaded or mapped, all carried in a race vest of 5 to 12 litres. Two rules sit above the list: your race's manual is the only version that counts, since requirements vary by event and can tighten with the forecast, and mandatory kit is a floor, not a plan. This page explains every item, what kit check is looking for, and what experienced runners carry beyond it.

I come at this from the food side of the sport: we supply ultra runners from UK trail races to the Marathon des Sables, I've spoken at the MDS expo twice, and the kit conversations before a first ultra are always the same mix of compliance anxiety and pocket Tetris. Here's the whole picture.

Why races mandate kit at all

Because ultras are long enough for summer to become winter, for a sprained ankle to mean two stationary hours on an exposed hillside, and for a wrong turn to put you beyond quick help. The mandatory list is the race director's answer to the question "what keeps a stopped runner alive until we reach them", which is also the right way to think about every item on it. Checks are real: at registration, at random mid-race spot checks, and missing items mean time penalties or a refused start depending on the event. Pack it all, every time, even when the forecast smiles.

The mandatory core, item by item

Waterproof jacket with taped seams. The most failed item at kit check. Taped means the stitching itself is heat-sealed; a showerproof or windproof shell doesn't pass and doesn't protect, and some events specify a minimum waterproof rating in the manual. Waterproof trousers join the list at many hill races.

Spare base layer. Carried dry and sealed, worn only if things go wrong. Dry fabric against skin is the cheapest hypothermia insurance in the sport.

Warm hat and gloves. Grams that matter disproportionately, because heat leaves fastest at the extremities and cold hands stop being able to open food, zips and phones exactly when you need them to.

Foil blanket or survival bag. For the stopped-runner scenario. A survival bag beats a blanket in real wind and weighs barely more.

Whistle. Six blasts, pause, repeat is the distress signal. Many vests have one built into the chest strap, which counts.

Phone, charged, on, and carrying the race director's number. In a waterproof pouch or bag, with the course GPX loaded where the event requires it.

Headtorch, plus a second light or spare batteries for anything touching darkness. Races that run through the night typically mandate two independent lights, and your main one should be bright enough to descend technical ground at 3am, not just to be seen.

Cup. UK trail racing has gone largely cupless; a foldable cup lives permanently in a vest pocket and weighs 10 grams.

Water capacity. Usually a specified minimum, commonly a litre in soft flasks, and remember checkpoint spacing is measured in terrain, not kilometres: a slow 10km trail section can take hours.

First aid basics. Typically a bandage or dressing, tape, and blister care, and the requirement is the kit plus the sense to use it. Build yours around feet, since feet end more ultras than anything else.

ID, and printed insurance where overseas races require it.

The emergency food requirement, done properly

Most mandatory lists include emergency food, and many specify a minimum, often in the region of several hundred calories, that must be sealed, separate from your race nutrition, and still in your vest at the finish. Two mistakes get made with it: treating it as an afterthought jelly-baby bag, and quietly eating it at mile forty. The clean solution is a single dense item that covers the number in one go and packs small enough to forget: one Phoenix Bar is up to 557 calories in 120 grams, which satisfies most races' reserve requirement as one sealed item, and it's soft enough to actually eat cold, tired and stressed, which is the entire point of the requirement. Whatever you choose, seal it, label it, and treat it as kit rather than food until the day it isn't.