Windows 10 has Windows location service turned on by default, Cortana and other apps use this service to find your device location. You may have noticed the icon with a circle in the notification area on the taskbar, which on hover over says ‘your location is currently in use’. If you’re concerned about your privacy and don’t want any apps or services to know your device location, do this.
Settings > Privacy > Location, click on Change and set Location for this device status to off, doing this also turns off location for your account. Cortana doesn’t work with this change, because this digital assistant needs location history to be enabled to work.
Windows location settings page also lets you control which apps can have access to your location and location history.
Do remember Apps that use technologies like Bluetooth or Wi-Fi scanning can still able to find your location despite Windows Location service has been turned off for your device.