He joins former IRA members and North Belfast incumbents Caral Ni Chuilin and Gerry Kelly, who have already been elected to the seat.
Mr Brett was a long-time aide to Nigel Dodds and holds a seat on Antrim and Newtownabbey Borough Council.
As the News Letter has previously reported, his story is an unorthodox one from a DUP perspective.
He is the product of a mixed Catholic/Protestant marriage, and grew up in a nationalist dominated area on the outskirts of Newtownabbey.
His brother, Gavin, was murdered in a sectarian drive-by shooting carried out by the UDA’s South East Antrim brigade in 2001 (he was assumed to have been a Catholic).
Mr Brett had spoken to the News Letter about this side of his life last year:
When he was nominated in March, Mr Brett had said: “As the son of a North Belfast mother from a working-class unionist community & of a father from a working-class nationalist community, I never expected this day to come.
“It would be the honour of my life to represent the Constituency that I love at Stormont. I won’t let you down.”
Lee Reynolds, former councillor and DUP strategist, wrote on Twitter this evening: “Congrats to the long man Phillip Brett on his election as a North Belfast MLA (with Brian Kingston soon to follow).
“I may have been his agent but all credit is due to him with the work, energy and enthusiasm he put into the campaign.”
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