National Grid customers here in New England are being warned to watch out for possible scam calls demanding immediate payment.

How to tell if the call is a scam:

1. The caller will demand credit card information or the account will be immediately shut off.

2. The caller does not know what account number they are calling on.

National Grid will contact customers who have a past due balance but will always offer them a payment plan and never will demand immediate full payment on the spot. Customers should always verify they are speaking with a reputable National Grid representative before giving out any personal account information. One way to verify this is to memorize the last five digits of your account and ask the rep to recite them back to you. If they can't or hesitate to then the call is most likely a scam.

If you believe you are being scammed, National Grid advises you to hang up immediately and dial 800-322-3223.