How do I thicken potato soup without flour?

Mash a portion of the cooked potatoes right in the pot. Russets release enough starch to thicken the whole batch on their own. If you want it thicker still, mash more — no roux or cornstarch required.

What potatoes are best for potato soup?

Russets. Their high starch content is exactly what breaks down into a creamy body. Yukon Golds are a decent second choice with a buttery flavor, but waxy red potatoes will leave you with a thin, brothy soup.

Why did my potato soup turn out grainy?

Almost always pre-shredded cheese. The anti-caking starch on bagged cheese doesn't dissolve smoothly. Shred cheddar from a block, and add it off the boil rather than while the soup is bubbling hard.

Can I freeze potato soup?

I'd skip it. Cream and potatoes both suffer in the freezer — the dairy separates and the potato cubes turn mealy. This one is best eaten within a few days of making it.

Home › Comfort Food › Slow Cooker Potato Soup

Slow Cooker Potato Soup (Thick, Creamy, No Blender Needed)

By Ami · September 11, 2026 · ★★★★★ 4.9 from 224 reviews · Jump to Recipe · Print

This slow cooker potato soup is the comfort food recipe I want the first genuinely cold evening of the year. It's thick enough to stand a spoon in, tastes exactly like a loaded baked potato, and there's no roux and no blender involved anywhere.

Slow cooker potato soup in a cream bowl topped with crispy bacon, shredded cheddar and chives

The potatoes thicken the soup themselves.

No roux, no cornstarch, no cream of anything. Russets are full of starch, and mashing a third of them against the side of the pot thickens everything naturally.
Ten minutes of prep, total. Dice, dump, walk away. It's the same low-effort approach as my broccoli cheddar soup, just with a heartier result.
Every topping is the good part. Bacon, cheddar, sour cream, chives — it's a baked potato bar that happens to be a soup.

Here's what you'll need.

Russets are essential here. Waxy potatoes like red or new potatoes hold their shape and won't give you that thick, velvety body.

Ingredients for slow cooker potato soup: diced russet potatoes, onion, garlic, broth, cream, cheddar, bacon and chives

Here's how it all comes together.

Step 1 — Dice the potatoes

Peel and cut the russets into even half-inch cubes. Even sizing matters more than exact sizing — mismatched pieces cook unevenly.

Dicing peeled russet potatoes into cubes on a wooden board

Step 2 — Load the pot

Add the potatoes, diced onion and garlic to the slow cooker along with a good pinch of salt. No sautéing needed.

Adding diced potatoes, onion and garlic to a white slow cooker

Step 3 — Add the broth

Pour in just enough chicken broth to barely cover the potatoes. Too much here and you'll be fighting a thin soup at the end.

Pouring chicken broth over diced potatoes in a slow cooker

Step 4 — Mash for body

Once the potatoes are fork-tender, mash about a third of them against the side of the pot. This is the entire thickening technique.

Mashing tender cooked potatoes against the side of a slow cooker to thicken the soup

Step 5 — Stir in the cream

Pour in the warmed heavy cream and stir. Warming it first keeps the soup from dropping temperature and stops any chance of curdling.

Pouring heavy cream into a slow cooker of potato soup

Step 6 — Melt in the cheese

Add the shredded cheddar in handfuls, stirring until each one disappears before adding the next. Dumping it all in at once makes it clump.

Stirring shredded cheddar cheese into creamy potato soup until melted

Finished bowl of loaded baked potato soup with bacon, melting cheddar, sour cream and chives

Things I learned while testing this recipe.

Shred your own cheese. Pre-shredded cheddar is coated in starch to stop it clumping in the bag, and that coating makes soup grainy. A block and a box grater fixes it.
Don't blend the whole pot. I tried an immersion blender and got potato glue. Mashing part of it keeps the texture interesting.
Bacon goes on top, not in. Cooked into the soup it turns soft and sad. Crisped separately and scattered over each bowl, it stays crunchy.
Cream at the end, off the boil. Dairy added early can split over a long cook. The last fifteen minutes is the right window.

Why this is worth making ahead.

It thickens overnight into something almost chowder-like — just loosen with a splash of broth when you reheat.
Prep the potatoes the night before. Store diced russets submerged in cold water in the fridge and they won't brown.
Double it easily. The recipe scales cleanly in a 7-quart cooker, which makes it a good option for feeding a group.

Here's what I'd serve with this.

Crusty bread or a warm roll — mandatory, as far as I'm concerned.
Mediterranean chickpea salad for something sharp and cold against all that cream.
Fried cabbage if you want a hot vegetable side that takes ten minutes.
Broccoli cheddar soup — set out both and let everyone build a bowl.
Apple crisp for dessert on a cold night.

Just in case you have leftovers.

Storing: Refrigerate in an airtight container for up to 4 days. I don't recommend freezing — dairy-based potato soup separates and the potatoes go mealy after thawing.

Reheating: Warm gently on the stovetop over low heat with an extra splash of broth or milk, stirring often. Avoid a hard boil, which can cause the cheese and cream to separate.

More comfort food recipes...

Creamy Chicken and Wild Rice Soup — the other cozy cream soup

Crockpot Mac and Cheese — no boiling, no baking

Chicken Pot Pie — creamy filling under a golden crust

Crockpot Beef Chili — thick, hearty and freezer-friendly

Slow Cooker Potato Soup

★★★★★ 4.9 from 224 reviews — Thick, creamy loaded baked potato soup made entirely in the slow cooker. No roux, no blender, and ten minutes of prep.

Prep 10 min · Cook 420 min · Total 430 min · Serves 8 · Category: Comfort Food · Cuisine: American

Ingredients

3 lb russet potatoes, peeled and cut into 1/2-inch cubes
1 large yellow onion, diced
4 cloves garlic, minced
4 cups chicken broth (just enough to barely cover)
3 tablespoons butter
1 cup heavy cream, warmed
2 cups sharp cheddar, freshly shredded
8 slices bacon, cooked crisp and crumbled
Sour cream and sliced chives, to serve
Kosher salt and black pepper

Instructions

Prep the potatoes. Peel and dice the russets into even 1/2-inch cubes.
Fill the cooker. Add the potatoes, onion, garlic, butter and a generous pinch of salt to the slow cooker insert.
Add broth. Pour in just enough chicken broth to barely cover the potatoes.
Slow cook. Cover and cook on low for 6 to 7 hours, until the potatoes are completely fork-tender.
Mash to thicken. Using a potato masher, mash about a third of the potatoes against the side of the pot.
Add cream. Stir in the warmed heavy cream.
Melt in the cheese. Add the shredded cheddar a handful at a time, stirring until each addition melts. Season to taste and serve topped with bacon, sour cream and chives.

Notes: For a lighter version, swap the heavy cream for whole milk plus 4 oz of cream cheese. Leaving the skins on adds texture and fiber — just scrub them well and dice a little smaller.

Nutrition (per serving, estimated): 438 calories · 14g protein · 36g carbs · 27g fat · 3g fiber

Slow Cooker Mediterranean Diet Cookbook cover

If cozy one-pot dinners are your whole personality, this cookbook is for you.

The Ultimate Slow Cooker Mediterranean Diet Cookbook is built around this kind of cooking — a handful of honest ingredients, one pot, long slow flavor and almost no active work. Comfort-food dinners that happen to be good for you.

Get the cookbook on Amazon

FAQ

How do I thicken potato soup without flour?: Mash a portion of the cooked potatoes right in the pot. Russets release enough starch to thicken the whole batch on their own. If you want it thicker still, mash more — no roux or cornstarch required.
What potatoes are best for potato soup?: Russets. Their high starch content is exactly what breaks down into a creamy body. Yukon Golds are a decent second choice with a buttery flavor, but waxy red potatoes will leave you with a thin, brothy soup.
Why did my potato soup turn out grainy?: Almost always pre-shredded cheese. The anti-caking starch on bagged cheese doesn't dissolve smoothly. Shred cheddar from a block, and add it off the boil rather than while the soup is bubbling hard.
Can I freeze potato soup?: I'd skip it. Cream and potatoes both suffer in the freezer — the dairy separates and the potato cubes turn mealy. This one is best eaten within a few days of making it.