The subsea cable that provides Tonga with broadband, and connects to the Southern Cross Cable via Fiji, has suffered a pair of cuts.
Both were in shallow water, with satellite connectivity provider SES Networks stating the cause could have been anchors.
The island has been without its cable connection since January 20, with its Digicel mobile network returning thanks to SES satellites.
"We have worked closely together with Digicel in the past in the Asia Pacific region, and now we're able to implement together our Signature Telecom Solution in a record time in Tonga," SES Networks vice president Imran Malik Khan said.
"We are especially pleased to help Tongan people get back online while efforts to repair the Tonga Cable System cable are taking place."
Local media reported on Monday that access to social media from Tonga had been filtered out to free up bandwidth.
Soon after the outage happened, Kacific used a Ku-band satellite to provide local ISP Ezinet with internet and voice capacity for priority communications.
The 827km cable between Tonga and Fiji that connects to the Southern Cross Cable went live in August 2013, and was funded jointly by the Asian Development Bank and the World Bank. It was later extended out to the Ha'apai and Vava'u islands in April last year.
The Australian government's Coral Sea subsea cable, being constructed by Vocus to connect Australia, Papua New Guinea, and Solomon Islands and funded through the foreign aid budget
Southern Cross Cables' NEXT subsea cable system between Australia, New Zealand, and the United States, being built by SubPartners
The Trident subsea cable system connecting Perth with Singapore via Indonesia
The Jupiter subsea cable connecting the US, Japan, and the Philippines and being built by a consortium including Facebook, Amazon, SoftBank, NTT Com, PLDT, and PCCW
The Asia-Pacific Gateway (APG) subsea cable connecting China, Hong Kong, Japan, South Korea, Malaysia, Taiwan, Thailand, Vietnam, and Singapore, owned by a consortium including China Telecom, China Unicom, China Mobile, NTT Communications, KT Corporation, LG Uplus, StarHub, Chunghwa Telecom, CAT, Global Transit Communications, Viettel, and VNPT, and being constructed by NEC
The Southeast Asia Japan 2 cable (SJC2), which will have 11 landing stations in Singapore, Thailand, Cambodia, Vietnam, Hong Kong, China, South Korea, Taiwan, and Japan, being built by NEC and funded by a consortium including China Mobile International, Chunghwa Telecom, Chuan Wei, Facebook, KDDI, Singtel, SK Broadband, and VNPT
The Bay to Bay Express Cable System (BtoBE), connecting Singapore and Hong Kong with the US, being funded by consortium including Facebook, Amazon Web Services (AWS), and China Mobile International, and being built by NEC