If you're installing Google Fiber Phone as your home landline, you'll need a minimum of one handset.
Things to consider
How do you want to set up your Google Fiber Phone service? Do you want to bring a current number with you, for example, your home landline number? Use a Google Voice number you already have? Get a new Google Fiber Phone number?
Do not cancel your existing service. If you're transferring a number from your home landline, your service must be active at the time Google Fiber Phone is installed.
You may want to install battery backup or another UPS (Universal Power Supply) to ensure service during an outage.
If you're bringing an existing phone number with you to Google Fiber Phone and have voicemail you want to save from your current service, contact your provider to ask them if they provide the ability to access and save your voicemail from a browser. Many carriers have a feature that lets you save voicemail to mp3 or wav files you can download to your computer.