Porridge Bars: An Easy Recipe and the Best UK Bars to Buy

Porridge bars are oat bars designed to give you roughly a bowl of porridge’s worth of oats in a form you can eat on the move. Shop-bought ones weigh 42 to 55g and carry about 180 to 225 calories, and a homemade baked banana porridge bar comes out at about 190 calories. Phoenix Bars work the other way round: a 120g oat bar with up to 557 calories that you can eat as it is or mix with water to make a bowl of porridge.

Written by James Frost, founder of Flaming Phoenix and the maker of Phoenix Bars. Updated 2 November 2026.

What is a porridge bar?

A porridge bar is a breakfast oat bar: mostly rolled oats, held together with fruit, syrup, milk or butter, and either baked soft or pressed firm. The name describes the job rather than the recipe. It stands in for the bowl of porridge you did not have time to sit down to, so most are made with plenty of wholegrain oats and sized as a breakfast rather than a sweet snack.

It sits between two neighbours. A flapjack bar is richer, with more butter and golden syrup and more calories per gram. A cereal bar is usually lighter and smaller, built from crisped grains rather than whole oats. Baked porridge bars, often made with banana and milk, are softer and more cake-like than either.

If you were looking for porridge fingers for babies, those are a different thing: soft fingers of oats and milk made for weaning. This guide is about bars for grown-up breakfasts on the go.

How many calories are in a porridge bar?

Usually 180 to 225 calories for a shop-bought bar and about 190 for the homemade bars below. A 40g bowl of porridge is about 150 calories made with water and about 310 with whole milk, so a typical porridge bar sits between the two.

The figure that changes most is size. Two bars that look alike can differ by half again in weight, so read the per-bar line on the label. If breakfast is where you are trying to get more calories in, my guides to high calorie porridge and high calorie breakfasts show how to build a bigger bowl.

How to make porridge bars

These baked banana porridge bars are soft, not too sweet and take five minutes to mix. The recipe makes 8 bars in a 20cm square tin, and the calories are worked from typical UK labels.

Ingredients

• 200g porridge oats
• 2 ripe bananas, about 200g peeled
• 200ml milk (any kind, including oat or soya)
• 60g smooth peanut butter
• 40g runny honey or maple syrup
• 1 teaspoon ground cinnamon
• 1 teaspoon baking powder
• A pinch of salt

Method

1. Heat the oven to 180C (160C fan, gas mark 4) and line the tin with baking paper.
2. Mash the bananas in a large bowl, then beat in the milk, peanut butter and honey.
3. Stir in the oats, cinnamon, baking powder and salt, and leave for 5 minutes so the oats soak up some of the liquid.
4. Spread into the tin, level the top and bake for 25 to 30 minutes, until firm in the middle and golden at the edges.
5. Cool in the tin for 15 minutes, then lift out and cut into 8.

Per bar: about 190 calories and 6g of protein.

Make them higher in calories: double the peanut butter to 120g and stir in 50g of chopped dark chocolate. That takes each bar to about 270 calories.

Keeping them: because they contain banana and milk, keep them in the fridge in an airtight box for up to 4 days, or wrap and freeze for up to 3 months. Warm one for 20 seconds in the microwave for a porridge-like breakfast.

Porridge bars you can buy in the UK

Figures are per bar from brand or major retailer labels, checked in November 2026. Recipes change, so check the pack you buy.

Phoenix Bars: the bar that turns into porridge

• 120g bar: 529 to 557 calories, 18 to 19g of protein and 60 to 66g of carbohydrate, depending on flavour.
• A pressed oat bar you can eat as it is, break into pieces, or crumble into water or milk to make porridge. It does not need hot water.
• Keeps for up to two years (12 months for Cherry Bakewell) and will not freeze or melt.
• Six flavours, made in the UK, £5.25 a bar.

I make Phoenix Bars, and they are the only bar here that turns back into a bowl of porridge. They are sold as high calorie bars for long days outdoors, early starts and anyone getting more calories in on a small appetite. Customers do it too: 55 of our published reviews mention mixing the bar with water or milk to make porridge.

Allergen note: Phoenix Bars contain soy, the Cherry Bakewell flavour contains almonds, and some flavours contain sulphites. The label carries a “may contain” warning for milk, egg, nuts, peanuts and sesame.

Quaker Porridge To Go

• 55g bar: about 225 calories, depending on flavour.
• Quaker says each bar has the same amount of oats as a bowl made with a 27g sachet of Oat So Simple.
• Can be eaten straight from the pack or warmed. Flavours include golden syrup, cinnamon and mixed berries.

The best-known supermarket porridge bar, sold in packs of two.

Stoats Porridge Oat Bars

• 42g bar: about 177 to 181 calories and around 3g of protein, depending on flavour.
• Made by an independent Edinburgh bakery with wholegrain Scottish oats and butter, and suitable for vegetarians.
• Flavours include raspberry and honey, blueberry and honey, apple and cinnamon, and orange and chocolate.

A soft, buttery bar that eats like a small flapjack.

How to turn a Phoenix Bar into porridge

1. Crumble the bar into a mug or bowl.
2. Add water or milk a little at a time, stirring until the bar breaks down.
3. Leave it for a minute, then add more liquid if you like it thinner.

Milk makes it richer; water is what you will have in a tent or on a trail. For a softer bowl with no effort in the morning, break the bar into a pot the night before with a splash of water, let it soak, then loosen it with a little more in the morning. More ways to use them are in how to use Phoenix Bars.

One customer training for a 170km race wrote that they “enjoyed mixing them with water to make a nutritious porridge for breakfast”.

Who are porridge bars best for?

• Commuters and early starts: a shop-bought bar, or a homemade one from the freezer, covers breakfast on the way out.
• Early training sessions: oats give you carbohydrate before a morning run or ride, if a bar sits well with you before exercise.
• Hikers and campers: a bar that doubles as porridge saves carrying a separate breakfast. See the lightest high calorie food for backpacking.
• Small appetites: half a bar mixed into a soft porridge with milk takes very little chewing, and my guide to what to eat when your appetite is low has more ideas.

Frequently asked questions

Are porridge bars healthy?

They are a practical way to eat oats when you cannot sit down to a bowl. Shop-bought bars vary a lot in sugar and fat, so compare the per-bar figures, and homemade bars let you control what goes in.

Can you heat a porridge bar?

Yes. Quaker suggests warming its bars, and homemade baked porridge bars warm well in 20 seconds in the microwave. A Phoenix Bar can be crumbled into warm or cold water or milk to make porridge.

Are porridge bars good for breakfast?

They are designed for it. On its own, a 42 to 55g bar is a light breakfast of about 180 to 225 calories, so add fruit, yoghurt or a milky drink if you need more, or choose a bigger bar.

Can you freeze porridge bars?

Homemade ones freeze well for up to three months. Wrap each bar so you can take one out the night before.

What is the difference between porridge bars and flapjacks?

Flapjacks are richer, bound with butter and golden syrup, and usually carry 430 to 480 calories per 100g. Porridge bars tend to be softer and lighter, often made with fruit and milk. Phoenix Bars are a pressed oat flapjack that also makes porridge.

Are there protein porridge bars?

Some breakfast bars add protein, and you can stir a scoop of protein powder into the recipe above. For bars built around added protein, see my guide to protein flapjacks.

Related guides

• High calorie overnight oats
• Calories in a bowl of porridge
• Protein flapjacks
• High calorie protein bars from Flaming Phoenix

Sources: Quaker and Stoats labels via the brands and major UK retailers, checked November 2026; ingredient figures from typical UK supermarket labels.