Deduplicate notifications on WearOS when using HA app on watch and phone

[altruizine]

Home Assistant Android app version(s):

• phone: 2026.2.1-full
• watch: 2026.2.1

Android version(s):

• phone: Android 16
• watch: WearOS 6.1

Device model(s):

• phone: Pixel 9 Pro
• watch: Pixel Watch 3

Home Assistant version:

• Core 2026.1.3

Last working Home Assistant release (if known):

• Did not work since at least 2026.12

Description of problem, include YAML if issue is related to notifications:
Non-targeted notifications are received by both the phone and the watch, but appear twice on the watch.

The phone seems to mirror its HA notifications to the watch, which has already received its own notification using its own HA app.

The issue is that when notification mirroring is disabled for the HA app, the watch receives not two, not one, but no notifications at all anymore.

Additional information:
This seems to be a common issue. There seems to be a fix that needs to be implemented in the phone app, see https://developer.android.com/training/wearables/notifications#avoid-dup.

[jpelgrom]

This is somewhat by design. Home Assistant allows you to send notifications to multiple targets. Your phone and watch are different targets. That means if you send the notification to both, it is expected you'll receive them on both. Then, if you mirror phone notifications you see the phone + watch notification on the watch.

The issue is that when notification mirroring is disabled for the HA app, the watch receives not two, not one, but no notifications at all anymore.

The behavior actually depends on the specific watch/watch companion app: some link notification permission for the watch and bridging from the phone, so you cannot disable them separately, but they are two different things.

This seems to be a common issue. There seems to be a fix that needs to be implemented in the phone app, see https://developer.android.com/training/wearables/notifications#avoid-dup.

All of these suggestions assume it is decided for you which notifications to bridge and which should not be bridged. Home Assistant cannot do that because it doesn't control the notification content and doesn't know about your watch companion app bridging setting.

To allow choice by you using the linked system, we'd need to add bridging tags to notifications, allow you to set them, and allow you to specify which tags to bridge and which tags not to bridge... but at that point it is a lot simpler to only send the notification to the phone or watch depending on what you'd like, instead of all devices, don't you agree?

[altruizine]

Thanks for your reply!

This is somewhat by design. Home Assistant allows you to send notifications to multiple targets. Your phone and watch are different targets. That means if you send the notification to both, it is expected you'll receive them on both. Then, if you mirror phone notifications you see the phone + watch notification on the watch.

Yes. So far so good.

The issue is that when notification mirroring is disabled for the HA app, the watch receives not two, not one, but no notifications at all anymore.

The behavior actually depends on the specific watch/watch companion app: some link notification permission for the watch and bridging from the phone, so you cannot disable them separately, but they are two different things.

I see. However, other apps that have separate WearOS clients, such as WhatsApp, seem to be able to send only one notification to each device (watch, phone), whereas with HA I do not seem to have that option—it's either two or none (as long as I have the WearOS app installed). How does WhatsApp do it?

All of these suggestions assume it is decided for you which notifications to bridge and which should not be bridged. Home Assistant cannot do that because it doesn't control the notification content and doesn't know about your watch companion app bridging setting.

To allow choice by you using the linked system, we'd need to add bridging tags to notifications, allow you to set them, and allow you to specify which tags to bridge and which tags not to bridge... but at that point it is a lot simpler to only send the notification to the phone or watch depending on what you'd like, instead of all devices, don't you agree?

I do understand your logic: The mirrored phone notification and the watch notification are two different things, and I specified I wanted them both, so I get them both on my watch. This seems correct; but it's also useless in the case of non-targeted (broadcast) notifications.

I guess what I'd prefer, then, is for the HA app to identify broadcast notifications and allow suppressing the generation of the obvious duplicate notification on the watch when the WearOS app is bridged to the phone app.

[jpelgrom]

The issue is that when notification mirroring is disabled for the HA app, the watch receives not two, not one, but no notifications at all anymore.

The behavior actually depends on the specific watch/watch companion app: some link notification permission for the watch and bridging from the phone, so you cannot disable them separately, but they are two different things.

I see. However, other apps that have separate WearOS clients, such as WhatsApp, seem to be able to send only one notification to each device (watch, phone), whereas with HA I do not seem to have that option—it's either two or none (as long as I have the WearOS app installed). How does WhatsApp do it?

To clarify, do you mean that

1. WhatsApp does have two different, independent toggles for
   • notification permission for the watch app
   • bridging phone notifications to the phone

or

2. Despite only having one toggle, when enabled WhatsApp is able to give you just one notification on the watch instead of two

?

For 1: no clue, that'd need testing.

For 2: they are probably using bridging tags/a message ID to prevent duplicates. This is possible because there is one message/notification to multiple devices. Home Assistant sends multiple notifications to multiple devices, so no shared ID. HA can't really change that as that's how you can have different platforms targeted at the same time. (This is my assumption, as WhatsApp isn't open source I can't check.)

[altruizine]

First, thank you @jpelgrom for taking the time to walk me through this!

To clarify, do you mean that

1. WhatsApp does have two different, independent toggles for

   • notification permission for the watch app
   • bridging phone notifications to the phone

or

2. Despite only having one toggle, when enabled WhatsApp is able to give you just one notification on the watch instead of two

I see two relevant toggles, and neither is in WhatsApp (on the phone or on the watch). Instead:

• On the watch, in system settings under Apps&Notification→App Notifications→Show All→WhatsApp, notifications are enabled.
• In the phone's “Watch” app, there's a toggle (for each app) whether to relay phone notifications to the watch. This toggle is enabled for WhatsApp.

The same is true for the Home Assistant apps on the phone and watch.

Not sure whether this maps to either alternative you mentioned; maybe there's still a misunderstanding. Earlier you said:

The behavior actually depends on the specific watch/watch companion app: some link notification permission for the watch and bridging from the phone, so you cannot disable them separately, but they are two different things.

Repeating my understanding in my words, for some phone/watch/app combinations, Android conflates (a) permission to relay notifications from phone to watch and (b) permission to bridge other info between watch and phone apps. But now, in your Alternative (1), “bridging” seems to refer to phone notifications, not other info. I guess that you actually mean that the phone bridges the information from HA that the watch should generate its own notification. Correct? (If not, could you please clarify?)

I believe that I have several apps on my watch that exchange data with their phone-app counterpart without requiring notification relaying to be on. I will definitely double check, maybe I'm wrong. If your theory is correct, then I understand now why HA notifications don't reach the watch if notification forwarding is off.

Now, for avoiding duplicates when notification forwarding is on:

For 2: they are probably using bridging tags/a message ID to prevent duplicates. This is possible because there is one message/notification to multiple devices. Home Assistant sends multiple notifications to multiple devices,

Makes sense so far.

… so no shared ID. HA can't really change that as that's how you can have different platforms targeted at the same time.

This is what I don't understand. Clearly, in the case of a single notifications picked up by multiple targets, all notifications trace back to a single originating call and message, as in the following example run with Developer Tools:

action: notify.notify
data:
  message: Test
  data:
    ttl: 0
    priority: high

Shouldn't it be possible to uniquely identify the notification on all devices?

[jpelgrom]

… so no shared ID. HA can't really change that as that's how you can have different platforms targeted at the same time.

This is what I don't understand. Clearly, in the case of a single notifications picked up by multiple targets, all notifications trace back to a single originating call and message, as in the following example run with Developer Tools:

action: notify.notify
data:
  message: Test
  data:
    ttl: 0
    priority: high

Shouldn't it be possible to uniquely identify the notification on all devices?

This technically should be possible with adjustments on the server side, but right now the notification targets (apps or other platforms) don't know it all originates from a single automation. There is no single ID for that action once it leaves your server.

(You can see exactly which data the app receives in Settings > Companion app > Notification history.)

The use case for somehow automatically deduplicating this is clear, but it's not something we can do with the current state. It also needs to avoid undermining basic concepts for how notifications work in HA.

[altruizine]

Wouldn't the notification-bridging filter described in the documentation I linked help to avoid relaying phone notifications to the watch? It looks like it's possible to statically prevent all phone notifications from being relayed (using a manifest declaration in the watch app), or to dynamically disable certain relayed notifications using addExcludedTags.

The logic would be that the watch app disables all or some phone notifications from being relayed, with the understanding that HA creates separate watch notifications anyway if needed.