Is Plain Flour the Same as All-Purpose Flour? A UK Guide
Is plain flour the same as all-purpose flour? Yes. Plain flour is the UK name for what US recipes call all-purpose flour: a white wheat flour with no raising agent. US all-purpose is often milled a little stronger, but you can swap them weight for weight in most recipes. Self-raising flour is plain flour with baking powder already mixed in.
At a glance
- Same flourplain flour in the UK is all-purpose flour in the US
- 2 tspbaking powder per 100g plain flour makes self-raising (Doves Farm)
- Bread flourthe US name for UK strong flour
- 80.9gcarbohydrate per 100g of plain flour (CoFID 11-886)
On this page
You've found an American recipe that looks perfect, and the first line says "2 cups all-purpose flour". Your cupboard has plain flour, self-raising flour and maybe a bag of strong white. Which one do you use? The good news is that the answer is simple. The names just differ on each side of the Atlantic, the same way as almond flour and ground almonds.
This guide matches up the UK and US flour names, explains what makes self-raising flour different, shows how to make it from plain flour, and gives the carbs in each from the UK's official food composition data. At the end there's a short section on what low-carb bakers use instead.
Is plain flour the same as all-purpose flour? UK and US names
Yes. Plain flour and all-purpose flour are both white wheat flour with nothing added to make it rise. Nelstrops, a UK family flour miller, puts it simply: plain flour is called all-purpose flour in the States, and strong flour is called bread flour.
There is one small difference worth knowing. UK plain flour is usually milled from softer wheat, while US all-purpose flour tends to be a little stronger, which means it has a bit more protein. The UK's CoFID dataset lists plain white flour at 9.1g of protein per 100g. King Arthur Baking, a US flour miller, gives 11.7% protein for its all-purpose flour, which it mills from hard wheat. More protein means more gluten can form, so a dough made with all-purpose flour can be slightly firmer and may take a little more liquid.
In practice, that rarely matters. For cakes, biscuits, pastry, pancakes and sauces, use plain flour wherever a US recipe says all-purpose, weight for weight. If a US recipe gives cups, convert it to grams first using our cups to grams guide: a US cup of plain flour weighs about 120g.
The other UK and US flour names
- Self-raising flour (UK) and self-rising flour (US): both are flour with a raising agent already mixed in. King Arthur Baking says US self-rising flour also contains salt, and it's milled from soft, lower-protein wheat. So they're close, but not identical.
- Strong flour (UK) and bread flour (US): higher-protein white flours made for yeast bread and pizza dough. Nelstrops says the two are essentially identical products with different names.
Plain vs self-raising flour: what's the difference?
The only real difference is the raising agent. Self-raising flour is plain flour with baking powder already blended through it, so cakes and scones rise without you adding anything else. Plain flour has nothing added, so you control the rise yourself, or leave it out for things that shouldn't rise, like shortcrust pastry or a white sauce.
| UK name | US name | Raising agent | Use for |
|---|---|---|---|
| Plain | All-purpose | None | Pastry, sauces, biscuits |
| Self-raising | Self-rising (also has salt) | Baking powder | Sponges, scones |
| Strong white | Bread flour | None | Yeast bread, pizza |
Names from Nelstrops and King Arthur Baking. Uses are typical, not fixed rules: plenty of cake recipes use plain flour plus baking powder.
You can see the raising agent in the nutrition data. CoFID lists self-raising flour at 342mg of sodium per 100g, against 2mg for plain flour. That extra sodium comes from the raising agent: baking powder is a mix of an acid and an alkali, and the alkali is usually sodium bicarbonate. Doves Farm's, for example, is sodium bicarbonate and acid calcium phosphate.
If an American recipe uses self-rising flour and also tells you to add salt, it's assuming the flour already contains some. With UK self-raising flour, you may want a small pinch of salt to match.
How to make self-raising flour from plain flour
If a recipe calls for self-raising flour and you only have plain, you can make your own. Doves Farm, a UK flour miller, gives this method:
- Measure 100g plain white flour and 2 tsp baking powder into a bowl and stir to combine.
- Sieve the flour blend into another bowl.
- Use the blend in place of self-raising flour.
Scale it up for bigger bakes: 200g of plain flour takes 4 tsp of baking powder, and 250g takes 5 tsp. Sieving matters, because it spreads the baking powder evenly so you don't get bitter pockets in the crumb. Doves Farm also notes that too much baking powder can give baked goods a soapy taste, so measure with a proper measuring spoon, levelled off.
Can you use self-raising flour instead of plain?
Sometimes. King Arthur Baking's advice for its self-rising flour is to use it in recipes that already include baking powder, and to leave out the recipe's baking powder and salt, because the flour already has them. Don't use self-raising flour for things that shouldn't rise, like shortcrust pastry, thickening a sauce, or yeast bread.
Carbs in plain and self-raising flour
All three white wheat flours have almost the same carbohydrate content. These figures come from the UK's Composition of Foods Integrated Dataset (CoFID 2021), per 100g.
| Flour (per 100g) | Carbs | Fibre | kcal |
|---|---|---|---|
| Plain (11-886) | 80.9g | 4.0g | 352 |
| Self-raising (11-888) | 79.6g | 4.0g | 348 |
| Strong white (11-887) | 79.2g | 3.3g | 353 |
CoFID 2021, Public Health England / Food Standards Agency, sheet 1.3 Proximates: "Flour, wheat, white, plain, soft" (11-886), "Flour, wheat, white, self raising" (11-888) and "Flour, wheat, bread/strong, white" (11-887). Carbohydrate excludes fibre, as on UK labels. Fibre is AOAC fibre.
Here's the maths for two common amounts of plain flour:
- 30g (about a quarter of a US cup): 80.9 × 30 ÷ 100 = 24.3g of carbohydrate.
- 120g (one US cup): 80.9 × 120 ÷ 100 = 97.1g of carbohydrate.
For self-raising flour, the same amounts give 79.6 × 30 ÷ 100 = 23.9g and 79.6 × 120 ÷ 100 = 95.5g. Swapping one white wheat flour for another makes almost no difference to the carbs in a bake.
Low-carb swaps for plain flour in keto baking
None of these wheat flours is low carb: a single US cup of plain flour has nearly 100g of carbohydrate. So for keto or low-carb baking, people usually swap the flour itself rather than the type of wheat flour.
- Almond flour plus a raising agent. Almond flour is the most common base for low-carb cakes, scones and biscuits. It behaves differently from wheat flour, so recipes usually add baking powder and egg for structure. Our guide to almond flour and ground almonds explains which to buy.
- A ready-made mix. Our low-carb baking mixes already contain the flours and raising agent, a bit like a low-carb self-raising flour. The Scone Mix, for example, lists almond flour, coconut flour, whey protein, golden linseed and baking powder among its ingredients. You rub in cold butter until it looks like breadcrumbs, then mix in an egg and Greek yoghurt. The product page says it makes about 8 medium scones.
- Oat fibre, for bulk. Oat fibre is a very light, fine powder. It's useful for adding bulk and texture, but it isn't a one-for-one swap for plain flour. The product page suggests adding it to baking, using it as a thickener, or mixing it into flour, and it doesn't give a fixed amount, so follow a recipe written for it.
For a side-by-side look at almond, coconut, oat fibre and other options, see our guide to low-carb flours.
The Scone Mix contains almonds (tree nuts, as almond flour) and milk (whey protein), according to the ingredients list on its product page. Always check the pack for full allergen information.
Free delivery is on orders over £30.
Frequently asked questions
Is all-purpose flour plain or self-raising?
All-purpose flour is plain. It's the American name for a white wheat flour with no raising agent added, which is what UK shops sell as plain flour. The US version of self-raising flour is called self-rising flour, and King Arthur Baking says it contains baking powder and a little salt as well as the flour.
Can I use plain flour instead of self-raising flour?
Yes, if you add a raising agent. Doves Farm, a UK flour miller, suggests mixing 2 tsp of baking powder with 100g of plain flour, stirring, then sieving it into another bowl. Use the blend weight for weight in place of self-raising flour. Without baking powder, a sponge or scone made with plain flour won't rise properly.
What is strong flour called in the US?
Bread flour. Nelstrops, a UK family flour miller, says strong flour and US bread flour are essentially the same product with different names. Both are higher-protein white wheat flours made for yeast bread and pizza dough. CoFID lists UK strong white flour at 11.3g of protein per 100g, against 9.1g for plain flour.
How many carbs are in plain flour?
About 80.9g of carbohydrate per 100g, according to the UK's CoFID dataset (food code 11-886), plus 4.0g of fibre. That works out at about 24.3g in a 30g portion, roughly a quarter of a US cup, and 97.1g in a 120g US cup. Self-raising flour is almost the same, at 79.6g per 100g.
What can I use instead of plain flour for low-carb baking?
None of the white wheat flours is low carb, so low-carb bakers usually use almond flour with a raising agent, or a ready-made baking mix. Oat fibre can add bulk and texture, but it isn't a one-for-one swap for plain flour. Almond flour behaves differently from wheat flour, so follow a recipe written for it.
Sources
- Public Health England / Food Standards Agency. Composition of Foods Integrated Dataset (CoFID) 2021: food codes 11-886 (plain), 11-888 (self raising) and 11-887 (bread/strong), sheets 1.3 Proximates and 1.4 Inorganics (sodium). Per-portion figures are our own calculations.
- Doves Farm. How to make self raising flour (100g plain white flour, 2 tsp baking powder) and Yeast and raising agents (what baking powder contains, too much baking powder).
- Nelstrops. What is strong white flour? (UK and US flour names).
- King Arthur Baking (US). How do you choose the right flour? (protein content of all-purpose, bread and self-rising flour) and How to substitute self-rising flour for all-purpose flour (salt and baking powder in self-rising flour, hard and soft wheat).
- Groovy Keto product pages: Scone Mix (ingredients, method, net carbs per scone, yield) and Oat Fibre (ingredients and suggested uses). Checked 26 October 2026.
