Note: The WWV Telephone Time-of-Day Service will be unavailable due to repairs on 13 March 2019 from 1400 to 2300 UTC. The WWVH TTDS (808)335-4363 will be in service during this repair.
The audio portions of the WWV and WWVH broadcasts can also be heard by telephone. The time announcements are normally delayed by less than 30 ms when using land lines from within the continental United States, and the stability (delay variation) is generally < 1 ms. When mobile phones or voice over IP networks are used, the delays can be as large as 150 ms. In the very rare instances when the telephone connection is made by satellite, the time is delayed by more than 250 ms.
To hear these broadcasts, dial (303) 499-7111 for WWV (Colorado), and (808) 335-4363 for WWVH (Hawaii). Callers are disconnected after 2 minutes. These are not toll-free numbers; callers outside the local calling area are charged for the call at regular long-distance rates.
The telephone time-of-day service is used to synchronize clocks and watches and for the calibration of stopwatches and timers. It receives about 2,000 calls per day.