If someone calls the 800 number, what caller id shows up when someone is calling?

You have the option of having the caller's information show up on your caller ID, which is the default, or your toll free number. Showing up as your toll free number can help to identify important calls when forwarding to a cell phone or similar multi-purpose phone. If you have voicemail enabled through 800.com you cannot reject these calls as they will defer to your carrier's voicemail system. 

To change your caller ID settings you will need to select the “Numbers” option from the column on the left of your browser window.

From here, you can either click on the number for which you wish to edit your preferences or you can hover over the 3 dots on the right and select “Manage” from the options that appear.

You will then need to enter the “Call Routing” category. Underneath the space where you entered your forwarding number there is a "Caller ID" section where you can toggle between the two options. Whichever is highlighted in blue is the selected configuration.