"Forever n then some," Grande wrote, sharing a number of photos alongside Gomez on Instagram.
The couple first made their relationship public in May, when they appeared together in Grande's music video for her song, 'Stuck with U'.
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The singer was previously engaged to comedian Pete Davidson in 2018, however they called off their engagement after five months.
While Grande's relationship with Davidson was highly publicised, the 27-year-old singer has kept her new relationship with Gomez relatively quiet.
Unlike comedian Davidson, who is best known for his role on Saturday Night Live, Gomez works as a luxury real estate agent.
According to Page Six, the 25-year-old has "previously represented mansions and estates that have sold in a range from $US5 million to $US12 million".