Illinois Overlay

In 1999, an all-services overlay was approved by the Illinois Commerce Commission (ICC) as the relief method for the 312 and 773 NPAs. Ten years later, implementation of NPA 872 is finally getting underway.

Relief Plan Timeline:
~ 08/7/09 -- Start of permissive 1+10-digit dialing
~ 11/7/09 -- End of permissive dialing and start of mandatory 1+10-digit dialing and earliest 872 NPA central office code activation date

The relief plan calls for mandatory 1+10 digit dialing for all direct dialed calls from NPAs in the overlay area. Permissive dialing allows subscribers to dial local calls within the overlay area on either a 7-digit or 1 plus 10-digit basis, with the 1 plus 10-digits being encouraged to prepare customers for the mandatory dialing requirement. Additionally, carriers are strongly encouraged to prepare their switches to begin sending 10 digits prior to the mandatory 1 plus 10-digit dialing customer conversion date.

For more details, please visit www.nanpa.com.