If you are the account owner, do the following:
Contract expiration is very easily found on MyVerizon.
Log into your account
On the next page scroll down and click on MORE ACTIONS
On the pop up screen choose the last option under the PLAN column, VIEW PLAN
Contract end date will be listed next to the image of your device.
Do this for each line on the account
Log on into your account. Bring your mouse arrow on MY VERIZON tab. When it opens click on MY PLAN AND SERVICES. On the top left side, you will see VIEW CONTACT END DATE. Click on that and it tells you what you are looking for.