The 20-year-old, who plays Mercy Olubunmi in the online Walford spin-off, was the only member of the main E20 cast not to be immediately picked up to transition across into the primary terrestrial episodes.
However, producers were so impressed by the strength and reaction to the character that they decided to write her into the main show alongside her teen counterparts Sam Attwater (Leon), Ricky Norwood (Fatboy) and Emer Kenny (Zsa Zsa).
Speaking of her signing, executive producer Diederick Santer said: "I'm pleased to announce that Bunmi will be following her E20 colleagues into EastEnders later this year.
"When I saw the completed episodes of E20 I knew I wanted Mercy in the big show too. Mercy's also been a huge hit with E20 viewers - she's funny, warm, sensitive and rather mysterious."
He added: "I'm delighted Bunmi will be bringing those qualities to the wider EastEnders audience."
Speaking to DS earlier this month, Mojekwu said: "In the beginning, I don't think they saw the strength of Mercy and then as I got into it, they really started to see that she has an impact and that she could go on and have a story."
It is believed that she has been contracted for six months, the same period of time as Attwater, Norwood and Kenny.
Meanwhile, combined viewing figures for EastEnders: E20 episodes and supporting content have staggered show bosses. Between January 8 and January 21, E20 material available via the official EastEnders website and the iPlayer platform has received 1.7 million views.
Of the numbers, Santer commented: "I'm knocked out by these figures! For our little side project, something that started life as an experiment, to go so big is very exciting. I'm delighted in particular that the 13 young London writers who wrote the series have reached such an audience with their first professional work."
> Click here to read our recent interview with Bunmi Mojekwu