A 5 lb bag of self-rising flour holds about 20.1 cups. The arithmetic is simple: 5 lb is 2,268 g, and one cup of self-rising flour weighs 113 g spooned and levelled, so 2,268 divided by 113 is 20.1 cups. Self-rising flour is all-purpose flour with baking powder and salt already mixed in, which is why it weighs slightly less per cup than plain all-purpose flour — 113 g compared with 120 g — and why a 5 lb bag holds more cups: 20.1 instead of 18.9. It is sold in 5 lb bags because it is used for quick breads, scones, pancakes and biscuits, and home bakers who use it go through it steadily.
Twenty point one cups is about ten batches of scones at 2 cups each, or twenty batches of pancakes at 1 cup each, or six quick loaves at 3 cups each. Self-rising flour is convenient because it removes a step: you do not need to add baking powder or salt, because they are already in the flour. But that convenience comes with a rule — never use self-rising flour in a recipe that calls for plain flour and adds its own leavening, or the bake will rise too much and then collapse. Knowing the bag holds 20.1 cups lets you plan a month of quick baking around one bag, and it tells you when the bag is nearly finished.
Bag of self-rising flour conversion table
The table below shows how many cups you get from fractions of a 5 lb bag, and how many cups of self-rising flour weigh how many grams. All figures use 113 g per cup, spooned and levelled.
| Amount | Cups (approx.) | Weight |
|---|---|---|
| 1/4 bag | 5.03 cups | 567 g |
| 1/2 bag | 10.05 cups | 1,134 g |
| 3/4 bag | 15.08 cups (about 15 1/8 cups) | 1,701 g |
| Full bag | 20.10 cups (about 20 1/8 cups) | 2,268 g |
| Cups | Grams (approx.) |
|---|---|
| 1 cup | 113 g |
| 2 cups | 226 g |
| 3 cups | 339 g |
| 4 cups | 452 g |
| 5 cups | 565 g |
| 10 cups | 1,130 g |
Self-rising flour is all-purpose flour with baking powder and salt already mixed in. It weighs slightly less per cup than plain flour (113 g vs 120 g), so a 5 lb bag holds more cups — 20.1 instead of 18.9. Use it only in recipes that call for it.
Worked examples
Scones for a weekend breakfast
A batch of eight scones uses 2 cups of self-rising flour, mixed with cold butter, sugar and milk — no baking powder needed, because it is already in the flour. One 5 lb bag holds 20.1 cups, so it covers ten batches — 80 scones. Cut the butter into the flour until it resembles coarse breadcrumbs, add the milk, and mix only until the dough comes together. Pat the dough out, cut the scones straight down without twisting the cutter, and bake at 220°C for 12 minutes. The scones should be golden on top and well risen, with a tender crumb inside.
Pancakes for a crowd
A batch of pancakes for six people uses 2 cups of self-rising flour, whisked with two eggs, milk and a little sugar — again, no baking powder needed. One 5 lb bag holds 20.1 cups, so it covers ten batches — sixty servings of pancakes. The baking powder in the flour gives the pancakes their lift, so do not add extra baking powder, or the pancakes will rise too much and then collapse. Cook them on a medium-hot griddle for two minutes a side, and serve with berries and maple syrup.
A quick soda bread for dinner
A quick soda bread uses 3 cups of self-rising flour, mixed with buttermilk and a pinch of salt, shaped into a round, scored with a cross, and baked at 200°C for 30 minutes. One 5 lb bag holds 20.1 cups, so it covers six loaves — six dinners with fresh bread. The baking powder in the flour does the leavening, so the bread does not need yeast or a long rise. Handle the dough as little as possible, because overworking it makes the bread tough. The loaf should sound hollow when tapped on the bottom, and it is best eaten the day it is baked.
How the figure is worked out
Think of the answer as a conversion, not a measurement. The package weight is a standard 5 lb (2,268 g) bag of self-rising flour. One cup of this ingredient weighs a known number of grams, so the cups in the package are the package weight divided by the cup weight. The method matters as much as the number: a spooned and levelled cup is the standard, and a scooped cup packs in more, which is why two bakers can get different cup counts from the same bag. The cup weight used here is 113 g per cup, spooned and levelled, sourced from King Arthur Baking.
Practical guidance
Self-rising flour has a shorter shelf life than plain flour, and that is the most important thing to know about it. The baking powder in the flour loses its strength over time — after about six months, it may not rise properly, and a bake made with old self-rising flour will be flat and dense. Plain flour keeps for a year, but self-rising flour should be used within six months of opening, and the bag should be dated when you open it. If you are not sure whether your self-rising flour is still active, test it: drop a teaspoon into hot water, and if it fizzes vigorously, it is still good. If it barely fizzes, throw it away and buy a fresh bag.
Never use self-rising flour in a recipe that calls for plain flour and adds its own baking powder or baking soda — the double leavening will make the bake rise too fast and then collapse, leaving a dense, sunken middle. And never use plain flour in a recipe that calls for self-rising flour without adding baking powder: a scone made with plain flour and no leavening will be flat and hard. The two flours are not interchangeable without adjusting the recipe. If you need to make self-rising flour at home, add 1 1/2 teaspoons of baking powder and 1/4 teaspoon of salt to each cup of plain flour, and whisk them together thoroughly. Measure self-rising flour by weight: 1 cup is 113 g, every time.
Frequently asked questions
Can I use self-rising flour instead of plain flour?
Only in recipes that call for it, or if you adjust the recipe. Self-rising flour already contains baking powder and salt, so using it in a recipe that adds its own leavening will make the bake rise too much and collapse. If a recipe calls for plain flour and baking powder, you can use self-rising flour and leave out the baking powder and salt — but check the amounts, because the baking powder in the flour is calibrated for a standard recipe.
How do I make self-rising flour at home?
Add 1 1/2 teaspoons of baking powder and 1/4 teaspoon of salt to each cup of plain all-purpose flour, and whisk them together thoroughly. Use it immediately, or store it in an airtight container — but homemade self-rising flour loses strength faster than the bought kind, so use it within a few weeks.
How long does self-rising flour keep?
About six months in an airtight container in a cool, dry place. The baking powder loses strength over time, so self-rising flour keeps for less time than plain flour. Test it before using: a teaspoon dropped in hot water should fizz vigorously. If it barely fizzes, throw it away.
How many cups are in a 2 lb bag of self-rising flour?
About 8 cups. A 2 lb bag is 907 g, and at 113 g per cup that divides out to 8.03 cups. That is about four batches of scones at 2 cups each, or eight batches of pancakes at 1 cup each.
Can I use self-rising flour for bread?
For quick breads like soda bread, yes — the baking powder does the leavening. For yeasted bread, no: self-rising flour is not designed for yeast, and the baking powder will interfere with the rise. Use plain bread flour for yeasted loaves, and self-rising flour for scones, pancakes, muffins and quick breads.