Out of Cornstarch, one case

Cornstarch substitute for pie filling

4 options, ranked, with the exact amount

Use thisBest of 4 options

Use Tapioca starch

1 tbsp for every 1 tbsp of cornstarch

For a fruit pie, use tapioca starch in the same amount as the cornstarch: it stays clear and does not weep after freezing. All-purpose flour also works at 2 tbsp per 1 tbsp cornstarch and is the usual thickener in apple pie, though it makes the juices cloudy. For a cream pie or lemon meringue pie, which has to hold a slice, use flour at 2 tbsp per 1 tbsp cornstarch; arrowroot, tapioca and potato starch do not set firm enough.

Verdict —: Tweak it
The tweak —: Toss it with the sugar and fruit and let the filling stand 15 minutes before it goes into the crust. Bake until the juices bubble thickly in the center, not only at the edge.
Best for —: berry, cherry and peach pies

One casethe full cornstarch card

Every option, one card

Ranked

Cornstarch substitutes compared
#	Substitute	Instead of 1 tbsp cornstarch	Verdict
1	Tapioca starchberry, cherry and peach pies	1 tbspTweak it	Tweak it
2	All-purpose flourapple and pear pie	2 tbspTweak it	Tweak it
3	Arrowroot powderrhubarb, cherry and berry fillings	1 tbspTweak it	Tweak it
4	Potato starchstovetop fruit fillings cooked briefly and cooled	1 tbspYou'll taste it	You'll taste it

What changesWhat changes, option by option4 options

Tapioca starch

neutral; the set is glossy and slightly stretchy

Cassava starch, also sold as tapioca flour. It thickens fruit juices to a clear, glossy gel and is the one thickener here that holds up through freezing and thawing.

Best for: berry, cherry and peach pies, pies and cobblers you will freeze, fillings you want clear and shiny
Prep: Toss it with the sugar and fruit and let the filling stand 15 minutes before it goes into the crust. Bake until the juices bubble thickly in the center, not only at the edge.
Suits: vegan, gluten-free
Where it fails: Cream pies, custard pies and lemon meringue, which stay loose. Too much makes a fruit filling gluey.

Quick-cooking tapioca granules are a different form: follow the amount on the box for pie and give them the same 15-minute stand. Under a lattice or crumb top, granules on the surface can stay hard.

All-purpose flour

neutral once cooked; pasty if undercooked

The thickener most kitchens have, and the most reliable substitute where the filling has to slice. It takes twice as much as cornstarch and gives an opaque filling.

Best for: apple and pear pie, cream pies, such as banana, coconut and chocolate, lemon meringue pie
Prep: For a fruit pie, toss it with the sugar and fruit. For a cooked filling, whisk it with the sugar before adding liquid and keep the filling at a gentle boil for 2 minutes after it thickens.
Contains: gluten
Where it fails: Berry and cherry pies, where it clouds the juices and dulls the color. Fruit pies thickened with flour weep when frozen and thawed.

Arrowroot powder

neutral taste

A root starch that thickens clear and is not weakened by acid, which suits tart fruit.

Best for: rhubarb, cherry and berry fillings, fruit fillings cooked on the stove and poured into a baked shell, grain-free pies
Prep: Toss it with the sugar before it meets the fruit so it disperses evenly.
Suits: vegan, gluten-free
Where it fails: Any filling made with milk or cream, where it turns slimy. In a very long bake it can thin out, so tapioca is the safer pick for a deep-dish pie.

Potato starch

neutral taste

It thickens fruit juices clear, but it is the starch that breaks down fastest when it is held at a boil, and an hour in the oven is a long boil.

Best for: stovetop fruit fillings cooked briefly and cooled, Passover baking, when other starches are off the table
Prep: Toss it with the sugar and fruit and take the pie out as soon as the center bubbles.
Suits: vegan, gluten-free
Where it fails: Long-baked fruit pies can come out runny, and cream pies will not set.

How it behaves in this recipe

In this recipeCornstarch

Pie asks two different things of cornstarch. In a fruit pie it thickens the juices as they bake so the slice does not flood the plate. In a cream pie or lemon meringue pie it sets a cooked filling firmly enough to cut. Root starches handle the first job well and fail at the second, which is why the answer splits by the kind of pie.

Tips for substituting cornstarch

5 tips

Fruit pie: tapioca starch or arrowroot in the same amount as the cornstarch, or flour at twice the amount. Mix it with the sugar first so it does not clump on wet fruit.
Cream and lemon meringue pie: 2 tbsp flour per 1 tbsp cornstarch, so ½ cup flour where the recipe has ¼ cup cornstarch. Boil gently 2 minutes after it thickens.
Bake a fruit pie until the filling bubbles thickly in the center. Starch that never reaches a boil never thickens, whichever one you use.
Cool the pie completely, at least 3 hours for fruit and 4 hours chilled for cream, before cutting. Every starch-set filling is loose while warm.
Do not thicken a pie filling for home canning with any of these. Only Clear Jel is tested for canned pie filling; otherwise can the fruit unthickened and thicken it when you open the jar.

Questions

5 questions

What can I use instead of cornstarch in apple pie?

All-purpose flour, at 2 tbsp for each 1 tbsp cornstarch, tossed with the apples and sugar. Apple juices are pale and the filling is not meant to be clear, so the cloudiness of flour does not show. Tapioca starch in the same amount as the cornstarch also works.

What can I use instead of cornstarch in lemon meringue pie?

All-purpose flour, at 2 tbsp per 1 tbsp cornstarch, cooked at a gentle boil for 2 minutes after the filling thickens. The filling will be opaque and a little less glossy but it will slice. Do not use arrowroot, tapioca or potato starch here: the filling stays soft and will not firm up in the refrigerator.

How much flour replaces 3 tablespoons of cornstarch in a pie?

6 tablespoons, which is ¼ cup plus 2 tablespoons. The conversion is always double. For tapioca starch or arrowroot, use 3 tablespoons, the same as the cornstarch.

Why is my pie filling runny after swapping the cornstarch?

Usually the filling never boiled, or the pie was cut warm. The juices have to bubble in the center for the starch to thicken, and the filling keeps setting as it cools. If you used arrowroot or potato starch in a pie that baked a long time, the starch may have broken down; use tapioca starch or flour next time.

Which substitute is right for a pie I want to freeze?

Tapioca starch, in the same amount as the cornstarch. Fillings thickened with cornstarch or flour release watery liquid when they thaw; tapioca stays set.