This answer is outdated. As of 2020 / Xcode 11.4 it's now possible to test push notifications in the simulator

See this full explanation in an answer below

Sorry to say, but you'll need to find some hardware to test this functionality.

Push notifications are not available in the simulator. They require a provisioning profile from iTunes Connect, and thus are required to be installed on a device. That also means you'll probably have to be accepted into the apple iPhone developer program and pay your $99.

On the bright side, with the iPhone OS 3.0 update, you can test this functionality on any device, including the first gen iPhones.

Testing push notifications using the Xcode 11.4 iOS Simulator

As of Xcode 11.4, it is now possible to simulate push notifications by dragging and dropping an .apns file onto the iOS simulator. The Xcode 11.4 release notes have the following to say about the new feature:

Simulator supports simulating remote push notifications, including background content fetch notifications. In Simulator, drag and drop an APNs file onto the target simulator. The file must be a JSON file with a valid Apple Push Notification Service payload, including the “aps” key. It must also contain a top-level “Simulator Target Bundle” with a string value matching the target application‘s bundle identifier.

simctl also supports sending simulated push notifications. If the file contains “Simulator Target Bundle” the bundle identifier is not required, otherwise you must provide it as an argument (8164566):

xcrun simctl push <device> com.example.my-app ExamplePush.apns

Example

Here is an example for such an .apns file, targeted towards the system settings app:

{
    "Simulator Target Bundle": "com.apple.Preferences",
    "aps": {
        "alert": "This is a simulated notification!",
        "badge": 3,
        "sound": "default"
    }
}

Dragging and dropping this onto the target simulator will present the notification and set the badge:

Now, to use this for debugging purposes, you only have to change the Simulator Target Bundle to your own app's identifier and adjust the payload to your debugging needs!

Apple has supporting push notification for simulators. iOS 13.4 and above or Xcode 11.4 and above.

as usually create Xcode project and implement a user notification and authorization permission.

run your application in simulator iOS 13.4 and above.

put your application in background.

1. Create an APNS payload file named "payload.apns"

{
  "aps": {
    "alert": {
      "title": "Test Push",
      "body": "Success! Push notification in simulator! ",
      "sound": "default"
    },
    "badge": 10
  },
  "Simulator Target Bundle": "com.company.app"
}

2. Drag and drop to your iOS simulator.

right now your push notification will appear on simulator.

And also you can simulate push notification by terminal

get your simulator identifier by opening Window->Devices and Simulators and choose your targeted simulator and right click and copy your identifier.

Now build a terminal command like

xcrun simctl push <simulator-identifier> <path-to-payload-file>

ex:

xcrun simctl push 27A23727-45A9-4C12-BE29-8C0E6D1E5360 payload.apns

run this command and simulate push notification in simulator

Xcode 11.4 Beta starts supporting push notification in Simulator

Simulator supports simulating remote push notifications, including background content fetch notifications. In Simulator, drag and drop an APNs file onto the target simulator. The file must be a JSON file with a valid Apple Push Notification Service payload, including the “aps” key. It must also contain a top-level “Simulator Target Bundle” with a string value matching the target application‘s bundle identifier.

simctl also supports sending simulated push notifications. If the file contains “Simulator Target Bundle” the bundle identifier is not required, otherwise you must provide it as an argument (8164566):

$ xcrun simctl push <device> com.example.my-app ExamplePush.apns

Release Notes: https://developer.apple.com/documentation/xcode_release_notes/xcode_11_4_beta_release_notes

Apart from @fredpi's answer, you can also use the Poes command-line tool. It allows us to quickly test remote push notifications on the iOS simulator without the hassle of creating a JSON payload file.

Poes --help
OVERVIEW: A Swift command-line tool to easily send push notifications to the iOS simulator

USAGE: Poes <options>

OPTIONS:
  --body, -b            The body of the Push Notification
  --bundle-identifier   The bundle identifier to push to
  --mutable, -m         Adds the mutable-content key to the payload
  --title, -t           The title of the Push Notification
  --verbose             Show extra logging for debugging purposes
  --help                Display available options

The following command could be enough to send out a simple push notification with a default title and body:

$ Poes --bundle-identifier com.wetransfer.app --verbose
Generated payload:

{
  "aps" : {
    "alert" : {
      "title" : "Default title",
      "body" : "Default body"
    },
    "mutable-content" : false
  }
}

Sending push notification...
Push notification sent successfully

Yes, you can check push notification on the simulator, but you have to use a library in your app named SimulatorRemoteNotifications. By which, by using just 4-5 steps, you can test push notification on the simulator.

They also provide PODs too:

pod 'SimulatorRemoteNotifications', '~> 0.0.3'

It looks like now we have very powerful lib https://github.com/ctreffs/SwiftSimctl

At least it's much more power than lib SimulatorRemoteNotifications which were mentioned here. And which was obsoleted also.

With macOS 13 and Xcode 14, when on Mac computers with Apple silicon or T2 processors, it’s now possible to receive real push notifications as didRegisterForRemoteNotificationsWithDeviceToken will return a real token.

See Xcode 14 release notes:

Simulator now supports remote notifications in iOS 16 when running in macOS 13 on Mac computers with Apple silicon or T2 processors. Simulator supports the Apple Push Notification Service Sandbox environment. Your server can send a remote notification to your app running in that simulator by connecting to the APNS Sandbox (api.sandbox.push.apple.com). Each simulator generates registration tokens unique to the combination of that simulator and the Mac hardware it’s running on.

https://developer.apple.com/documentation/xcode-release-notes/xcode-14-release-notes

For a more complete answer since Xcode 11.4 and as of Xcode 12.4:

1. Simulator supports simulating remote push notifications, including background content fetch notifications. In Simulator, drag and drop an APNs file onto the target simulator. The file must be a JSON file with a valid Apple Push Notification Service payload, including the “aps” key. It must also contain a top-level “Simulator Target Bundle” with a string value that matches the target application’s bundle identifier. simctl also supports sending simulated push notifications.

2. Notification Service Extensions do not work in simulated push notifications. The mutable-content key is not honored. (55822721)

Reference: Xcode 11.4 Release Notes