The government seismologists said the quake had a magnitude of 6.0 and was at a depth of 6.2 miles. It occurred at 2 p.m. EDT Wednesday.
Its epicenter was 165 miles northwest of Hihifo, Tonga, and 1,630 miles north northeast of Auckland, New Zealand.
The USGS announcement did not mention whether a tsunami was expected.
An earthquake and a following tsunami killed more than 180 people on Samoa, American Samoa and nearby islands on Sept. 29. That earthquake was at 8.3 magnitude.