Wide Area Telephone Service

In U.S. telecommunications, a Wide Area Telephone Service (WATS) is a toll service offering for customer dial-type telecommunications between a given customer [user] station and stations within specified geographic rate areas employing a single access line between the customer [user] location and the serving central office. Each access line may be arranged for either outward (OUT-WATS) or inward (IN-WATS) service, or both.

In other words, with "outward WATS" the calling party may make an unlimited number of long distance calls (toll calls), for a fixed price, within pre-determined time and distance constraints. With long distance costs at historic lows, this type of arrangement has become common, and instead of "outward WATS" it is known simply as a "flat-rate plan."

With "inward WATS," subscribers are issued a toll-free telephone number, typically beginning with a designated toll-free area code. Inward WATS service was introduced by AT&T in 1967 in order to reduce time spent by operators processing toll-collect calls for businesses. The first inward WATS area code issued was 800, with 888, 877, and 866 area codes being planned and implemented in the 1990s. Telephone users within a designated area may call an inward WATS telephone number without having to pay a toll charge – the recipient pays for the calls at a flat rate or other predetermined rate. Growth of inward WATS exploded in the 1980s as technology allowed companies to build business with nationwide toll-free 800 numbers which could ring at multiple call-centers.

"Inward WATS" service is available with Automatic Number Identification (ANI), a form of super-Caller ID.

Offerings for fixed-rate inter-LATA and intra-LATA services are measured by zones and hours.