Born on November 5, 1913, Umeno Sumiyama and Koume Kodama were 107 years and 300 days old as of September 1, according to a statement from Guinness World Records on Monday.
They were born on Shodo Island, Kagawa prefecture, into a family of 13. The pair now live in separate care homes.
When they were born, being a twin was reason enough to get bullied, according to the statement, and Sumiyama and Kodama lived apart from an early age.
Kodama left Shodo Island after elementary school and later married someone outside the island, so the twins ended up living more than 300 kilometers (186 miles) apart, said Guinness World Records.
They mainly reconnected at weddings and funerals, but around the age of 70 they went on several Buddhist pilgrimages together.
The pair later joked about breaking the record for the oldest living identical twins, previously held by fellow Japanese nationals Kin Narita and Gin Kanie, but never expected to do so.
Guinness World Records said that, on their 99th birthday, Sumiyama looked at a photo of the then-record holders and said: "I think we look younger."
Guinness World Records sent the twins their certificates by post due to Covid-19.
Care home staff said Sumiyama burst into tears when she saw the certificate.
"Koume, whose memory is not what it once was, sadly couldn't fully comprehend the significance of receiving the certificate," continues the statement.
The oldest male identical twins ever verified by Guinness World Records were Dale and Glen Moyer, from the US, who both reached the age of 105. Born in 1895, they became the oldest living twins on January 23, 2000.
Japan is known for its supercentenarians -- a person who is 110 years old or older -- and many records have been achieved in the country, said Guinness World Records.
Among their number is the oldest person living, Kane Tanaka, who is 118. Tanaka has twice survived cancer, lived through two global pandemics and loves fizzy drinks.