Tems was born in Lagos in 1995. Her father is British, but her parents separated when she was five and she was brought up by her mum. At school she was noticed by her music teacher and she learnt the piano. She would practice singing with her brother's guitar accompaniment. She attended Dowen College in Lekki and studied and graduated in economics in Johannesburg. In 2018 she recorded Mr Rebel - a song of her own composition.
In August 2019, Tems released the single Try Me. It became a major hit and currently has over 3.7 million views on YouTube. In 2020, DJ Edu chose her as one of "ten artists to watch" that year. She was recruited that year by American singer Khalid to join him and fellow Nigerian Davido on an Afrobeats remix of "Know Your Worth".