***

title: "CheckShippingEligibilityCheckerFn"
generated: true
---------------

<GenerationInfo sourceFile="packages/core/src/config/shipping-method/shipping-eligibility-checker.ts" sourceLine="138" packageName="@vendure/core" />

A function which implements logic to determine whether a given [Order](/current/core/reference/typescript-api/entities/order#order) is eligible for
a particular shipping method. Once a ShippingMethod has been assigned to an Order, this
function will be called on every change to the Order (e.g. updating quantities, adding/removing
items etc).

If the code running in this function is expensive, then consider also defining
a [ShouldRunCheckFn](/current/core/reference/typescript-api/shipping/should-run-check-fn#shouldruncheckfn) to avoid unnecessary calls.

```ts title="Signature"
type CheckShippingEligibilityCheckerFn<T extends ConfigArgs> = (
    ctx: RequestContext,
    order: Order,
    args: ConfigArgValues<T>,
    method: ShippingMethod,
) => boolean | Promise<boolean>
```