# receive(on:options:) Specifies the scheduler on which to receive elements from the publisher. ``` func receive(on scheduler: S, options: S.SchedulerOptions? = nil) -> Publishers.ReceiveOn where S : Scheduler ``` ## Parameters `scheduler` The scheduler the publisher uses for element delivery. `options` Scheduler options used to customize element delivery. ## Return Value A publisher that delivers elements using the specified scheduler. ## Discussion You use the [`receive(on:options:)`](/documentation/Combine/Publisher/receive(on:options:)) operator to receive results and completion on a specific scheduler, such as performing UI work on the main run loop. In contrast with [`subscribe(on:options:)`](/documentation/Combine/Publisher/subscribe(on:options:)), which affects upstream messages, [`receive(on:options:)`](/documentation/Combine/Publisher/receive(on:options:)) changes the execution context of downstream messages. In the following example, the [`subscribe(on:options:)`](/documentation/Combine/Publisher/subscribe(on:options:)) operator causes `jsonPublisher` to receive requests on `backgroundQueue`, while the [`receive(on:options:)`](/documentation/Combine/Publisher/receive(on:options:)) causes `labelUpdater` to receive elements and completion on `RunLoop.main`. ``` let jsonPublisher = MyJSONLoaderPublisher() // Some publisher. let labelUpdater = MyLabelUpdateSubscriber() // Some subscriber that updates the UI. jsonPublisher .subscribe(on: backgroundQueue) .receive(on: RunLoop.main) .subscribe(labelUpdater) ``` Prefer [`receive(on:options:)`](/documentation/Combine/Publisher/receive(on:options:)) over explicit use of dispatch queues when performing work in subscribers. For example, instead of the following pattern: ``` pub.sink { DispatchQueue.main.async { // Do something. } } ``` Use this pattern instead: ``` pub.receive(on: DispatchQueue.main).sink { // Do something. } ``` > Note: ``doc://com.apple.Combine/documentation/Combine/Publisher/receive(on:options:)`` doesn’t affect the scheduler used to call the subscriber’s ``doc://com.apple.Combine/documentation/Combine/Subscriber/receive(subscription:)`` method. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)