Best Vegan Energy Bars UK: 9 Compared on the Label

Written by James Frost, founder of Flaming Phoenix. Updated October 2026.

The best vegan energy bars in the UK, on labels checked in October 2026, are Phoenix Bars for a meal's worth of calories in a compact bar (up to 557 calories in 120g), Trek Protein Flapjack as an everyday snack bar (227 calories) and Styrkr BAR50 for racing (50.4g of carbohydrate in 70g).

I make Phoenix Bars, and they are in this list on the same terms as everything else. How I checked: every figure comes from the brand's own page or a UK retailer listing that I opened in October 2026, and each page is linked in the sources at the foot. "Vegan" here means the page says "vegan", "suitable for vegans" or "vegan friendly"; I then read the ingredients for honey, milk, whey and collagen, and noted where the protein comes from. I have not taste-tested the other bars, and no brand paid to be included.

How to tell if an energy bar is really vegan

Read the ingredients, not the front of the pack, because honey, milk sugars, whey, casein and collagen all turn up in bars that look plant-based.

• Honey. Nature Valley Crunchy Oats & Honey contains 3% honey and is labelled suitable for vegetarians, not vegans. Veloforte says its Classico and Ciocco bars "contain a little honey", while its Di Bosco bar is vegan.
• Milk in small amounts. Nature Valley Protein Peanut & Chocolate lists lactose and a natural flavouring made from milk, so it is vegetarian, not vegan.
• Whey, casein and collagen. A Grenade protein bar's 20g of protein comes from whey protein isolate, calcium caseinate and bovine collagen.
• No claim at all. The Clif Bar Chocolate Chip listing I checked at Hancocks makes no vegan claim and says it may contain milk. Check the brand's current wording before you assume either way.

A "may contain milk" line is a different matter. GOV.UK's guidance on vegan labelling says there is no legal definition of vegan food in UK law, and that a vegan label means no animal ingredients were used on purpose; it is not a promise that a trace from the factory is impossible. Trek, Deliciously Ella and Phoenix Bars all carry a may-contain-milk line alongside their vegan claim. If you avoid milk for allergy reasons, go by the allergen line, not the vegan badge.

The best vegan energy bars, by what you need them for

Nine bars that pass the ingredient check, grouped by the job they do best. Calories and protein are per bar from the label.

• Meal-sized calories in a compact bar: Phoenix Bars. From 529 to 557 calories in only 120g (4.4 to 4.6 per gram), with up to 66g of carbohydrate and 18 to 19g of protein from soy protein isolate and pea protein crisps. Labelled vegan and gluten-free, and made with gluten-free oats; the label says they are made where milk and egg are handled. £5.25 a bar. You can order a pack of Phoenix Bars direct.
• A bigger meal bar: a heavier 150g meal bar. Over 600 calories in 150g, with 26g of protein from pea protein and peanuts, about 4.0 calories per gram. The biggest and heaviest bar here.
• Everyday protein flapjack: Trek Protein Flapjack Cocoa Oat. 227 calories and 9g of soya protein in 50g, with 25% gluten-free oats. Labelled vegan friendly. A desk-drawer or day-walk snack; at 227 calories you need two or three to match one Phoenix Bar.
• Race carbohydrate: Styrkr BAR50 Dark Chocolate Chip. 249 calories and 50.4g of carbohydrate in a 70g crisp-rice bar, described as 100% vegan and gluten-free on Styrkr's page. With 2.5g of protein it is fuel for the hard part of a ride or run, not a snack that keeps you full; the best energy bars for long-distance cycling comparison covers it on the bike.
• Fast sugar with added B12: KMC NRG Bar. 85g with 83g of carbohydrate, almost all sugar, which works out at roughly 330 calories, plus electrolytes and a B-vitamin blend that includes B12. Gluten-free; Mountain Warehouse's page calls it "Vegan" in one place and "often Vegan" in another, so check the wrapper.
• Fruit and nuts: Veloforte Di Bosco. 238 calories and 4.5g of protein in 55g of dried fruit, almonds, pistachios and gram flour, vegan and gluten-free on Veloforte's page. Stick to Di Bosco, Avanti, Zenzero or Mocha if you are vegan.
• Smallest and simplest: Nakd Cocoa Delight. 135 calories and 3.3g of protein in 35g of dates, cashews, raisins and cocoa, vegan and gluten-free on Premcrest's listing. A snack rather than fuel for a big day.
• Supermarket oat bar: Deliciously Ella Cacao & Orange. 209 calories and 3.5g of protein in 50g, with 49% gluten-free oats, labelled suitable for vegans.
• Protein per calorie: Free Soul vegan protein bar. 164 calories and 15g of protein from a three-source plant blend (the page does not name the sources), vegan friendly and gluten-free, with 0.5g of sugar, according to Free Soul's page. Built for protein, not calories: it has under a third of the calories of a Phoenix Bar.

Where does the protein in vegan bars come from?

Mostly soya and pea protein isolates, peanuts and other nuts, and the bars with the most protein per calorie use isolates rather than whole nuts.

Here is protein per 100 calories, worked out as protein per bar divided by calories per bar, times 100, from the label figures above:

• Free Soul: 9.1g (three plant sources, not named)
• 150g meal bar: about 4.3g (pea protein and peanuts)
• Trek: 4.0g (soya)
• Nakd: 2.4g (cashews)
• Veloforte Di Bosco: 1.9g (almonds, pistachios, gram flour)
• Deliciously Ella: 1.7g (oats)
• Styrkr BAR50: 1.0g (rice)
• KMC NRG Bar: none

So pick by the job. If protein is the point, a protein bar wins by a distance. If calories for a long day are the point, a protein bar is the wrong tool: you would need more than three Free Soul bars to match the calories in one Phoenix Bar. Phoenix Bars carry up to 19g of protein, and their main job is calories.

What are the best vegan cereal bars in the UK?

For a supermarket cereal bar that is actually vegan, Deliciously Ella's baked oat bars (209 calories, gluten-free oats) and Nakd are the easy picks, and Trek's flapjack adds 9g of soya protein.

The common trap is honey. Nature Valley Crunchy Oats & Honey, the best-known oat bar on the shelf, lists 3% honey on Tesco's page and says suitable for vegetarians, not vegans. If you would rather make your own, the vegan flapjacks recipe uses golden syrup and a vegan baking block in place of honey and butter, and homemade high calorie bars covers denser versions.

Do vegan energy bars need vitamin B12?

No. A bar does not need added B12 to be a good vegan bar, because B12 is better covered by fortified foods or a supplement you take every day anyway.

The NHS guidance on the vegan diet says that "sources for vegans are limited and a vitamin B12 supplement may be needed", and lists fortified breakfast cereals, unsweetened soya drinks fortified with B12, and yeast extract such as Marmite. Of the nine bars here, only the KMC NRG Bar lists added B12. The rest, Phoenix Bars included, make no B12 claim, which is fine as long as your B12 comes from somewhere else.

Common questions

Which vegan bars work as a meal replacement?
Phoenix Bars (up to 557 calories) and the heavier 150g meal bar above (about 600) are meal-sized, but neither is sold as a nutritionally complete meal replacement. They are large, calorie-dense bars for a long day. Our best meal replacement bars UK comparison covers the products built for that job.

Are vegan energy bars gluten-free?
Most of the nine here are labelled gluten-free, but not all, so look for the gluten-free claim on the label rather than gluten-free oats in the ingredients. Oats, cross-contamination and the 20 parts per million rule are explained in our comparison of the best gluten free energy bars UK.

Which vegan bar is best for gaining weight?
The one with the most calories you will happily eat, ideally one that covers a 500-calorie surplus in a single bar, as Phoenix Bars do. Our guides on how to gain weight on a vegan diet and the best energy bars for weight gain go further.

Which vegan bar is best for a long hike or an ultra?
That depends on distance and how you eat on the move. Weight carried matters on a hike, gut comfort on an ultra. See the best energy bars for hiking, the best energy bars for ultra running and our guide to vegan endurance nutrition. If weight carried is the deciding factor, the highest calorie bars in the UK are ranked per gram, including our own high calorie bars.

Sources, checked October 2026: GOV.UK, vegan food labelling; NHS, the vegan diet; product pages for the 150g meal bar (McGrocer, Cotswold Outdoor), Trek, Deliciously Ella, Nature Valley and Nature Valley Protein (Tesco), Styrkr, KMC NRG Bar (Mountain Warehouse), Veloforte, Nakd (Premcrest), Free Soul, Grenade (Ocado) and Clif Bar (Hancocks). Flaming Phoenix is not affiliated with any other brand named here, and all trademarks belong to their owners.