How to make overnight oats: the easy ratio, flavors and meal prep

The short answer: Overnight oats are rolled oats soaked in milk in the refrigerator until they turn soft and creamy, with no cooking needed. **Here's how to make overnight oats: stir ½ cup of old-fashioned rolled oats, ½ cup of milk, ¼ cup of plain Greek yogurt, 1 tablespoon of chia seeds, 1 to 2 teaspoons of maple syrup and a pinch of salt together in a jar.

Cover it and refrigerate it for at least 4 hours or overnight, then add fruit and eat it cold or warmed.** Below are the basic ratio, eight flavor ideas, how long they keep and how to prep a week of jars at once.

I love cooking, and overnight oats are one of the simplest make-ahead breakfasts there is. Each jar takes about five minutes the night before.

The basic overnight oats ratio

The easy rule is 1 part oats to 1 part liquid, plus a little yogurt for creaminess. Here is one serving.

Which oats work best? Old-fashioned rolled oats give the classic texture. Quick oats get soft and pasty overnight, and steel-cut oats stay chewy unless you soak them a full 12 hours or more.

How to make overnight oats, step by step

1. Pick a jar. A 12- to 16-ounce jar or container with a lid holds one serving with room for toppings.
2. Add the dry ingredients. Put in the oats, chia seeds and salt. Skip the oats and the same jar becomes chia seed pudding.
3. Add the wet ingredients. Pour in the milk, yogurt, maple syrup and vanilla.
4. Stir well. Mix until no dry oats are left at the bottom. If you're using chia, stir again after 10 minutes so it doesn't clump.
5. Refrigerate. Cover and chill for at least 4 hours, or overnight.
6. Top and eat. Stir, loosen with a splash of milk if it's too thick, and add fruit, nuts or nut butter.

Want them warm? Microwave the jar, uncovered, for 1 to 2 minutes, stirring halfway. Use a microwave-safe container, and check that it's heated through.

Overnight oats flavor ideas

Start with the basic ratio, then add these mix-ins the night before. Save crunchy toppings for the morning.

For more protein, use more Greek yogurt, stir in a spoonful of nut butter or add a scoop of protein powder with an extra splash of milk. For less sugar, skip the syrup and sweeten with mashed banana or grated apple.

How long do overnight oats last?

Most overnight oats keep up to 4 days in the refrigerator, which is why they work well for meal prep. Keep them cold at 40°F or below, the refrigerator setting on FoodSafety.gov's cold food storage chart. Add fresh fruit that browns, such as banana and apple, on the day you eat it.

Because the jars contain milk and yogurt, they shouldn't sit at room temperature for long. The USDA's danger zone guidance says perishable food shouldn't be out of the fridge for more than 2 hours, or 1 hour above 90°F. If you take a jar to work, pack it with an ice pack or put it straight into the office fridge.

Meal prep a week of overnight oats

Mixing four or five jars at once takes about 15 minutes.

1. Line up the jars and add the oats, chia and salt to each one.
2. Mix the wet ingredients in a large measuring cup: 2 cups of milk, 1 cup of yogurt, maple syrup and vanilla for four jars. Pour an even amount into each.
3. Add flavor mix-ins so each jar is different, if you like variety.
4. Label the lids with the flavor and the day they were made.
5. Refrigerate and eat within 4 days.

For a full Sunday prep plan, including lunches and dinners, see our meal prep ideas. For plant-based options, our vegetarian meal prep ideas use the same jars.

Common overnight oats mistakes

• Too thick: add another splash of milk in the morning. Chia and yogurt both absorb liquid as they sit.
• Too runny: add a spoonful of chia or oats and give it another hour.
• Dry layer at the bottom: stir well, including the bottom of the jar, before chilling.
• Soggy toppings: keep granola, nuts and crunchy cereal separate until you eat.

Plan your breakfasts

Breakfast is easier when it's already on the plan. Write the week's oat flavors next to your dinners, and the grocery list writes itself. For more healthy breakfast options beyond oats, that guide covers eggs, yogurt bowls and meal-prep mornings. More balanced plates live under healthy recipes. Curious about the nutrition behind the jar? Read is oatmeal good for you.

• Meal Planner & Grocery List, $3.99. A weekly meal planner, a grocery list, recipe cards, a pantry and freezer inventory and a meal prep checklist for your Sunday jar session.
• Family Recipe Binder, $6.99. Save your family's favorite oat flavors and ratios on their own pages.

Browse all our Printables or the Home shop. For a bigger-picture routine, see our guide to how to meal plan and our morning routine ideas. Want a no-soak option some mornings? Our healthy smoothie recipes blend in minutes. Prefer a hot high-protein bite instead? Bake a tray of egg bites.

Want stovetop and baked options too? See our oatmeal recipe guide. For a wider morning menu beyond oats, browse our breakfast ideas. Prefer a savory overnight egg bake instead of oats? Make a breakfast strata.

Compare oats with other options in the healthiest breakfast guide, which explains the protein-fiber-fat formula.