The Australian women have been honoured by their state government, Emirates 24/7 reports.
Hazel Gillbee, 84, Clarise Artis, 97, Trudy Bullivant, 90, and Nancy Ayres, 89, broke the record during a swim in Melbourne on August 19.
Officials confirmed their time of 5 minutes and 45 seconds had broken the record for the 4x50m relay.
The oldest of the women, Clarise, only started swimming backstroke at the age of 86.
She said: "It's a bit of inspiration for younger people to get off their bums and do something."
State governor Alex Chernov celebrated the women's achievements by inviting them for afternoon tea at Government House last Friday (August 24).
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