There are 3 ways to find the serial number of your HomePod. You can look at the bottom of the device, check it through the settings app and also through the Home app. Knowing the serial number of your HomePod is key for when you register your device with Apple and when you need support. The steps are below:
Find your HomePod serial number in the Settings app
1) Your iPhone, iPad or iPod Touch must be running iOS 11.2.5 or later. Open the Settings app.
2) At the top of Settings is your Apple ID, tap it.
3) Scroll down and find your HomePod in the list of devices. Tap on it.
4) You will now see your Serial Number.
Find your HomePod serial number in the Home app
1) Again your iPhone, iPad or iPod Touch must be running iOS 11.2.5 or later. Open the Home app.
2) Tap the Home tab.
3) Press and hold the icon for your with 3D touch. You will have to do a long-press if your iOS device doesn’t have 3D touch.
4) Tap details.
The serial number will be displayed at the bottom.