The Sugababes singer, 31, shared her excitement on Friday night (22 May) after Alex Partakis popped the question.
She wrote: "Delighted to share the news that my gorgeous @alexpartakis proposed last night! Am the happiest girl alive and can't wait to be Mrs HP x."
He in turn posted a matching sweet message, saying: "Am the happiest man in the World today. @Heidi_range said yes! Can't wait to spend the rest of our lives together xxx."
Delighted to share the news that my gorgeous @alexpartakis proposed last night!Am the happiest girl alive and can't wait to be Mrs HP x— heidirange (@Heidi_range) May 22, 2015
Dancing On Ice star Heidi and property developer Alex have been dating for a year and a half after being 'set up' by her personal trainer in early 2014.
They have been inseparable ever since.
Just this week, 'Push The Button' star Heidi hinted that she was hoping Alex would propose.
She told the Scottish Daily Record: "I try not to think about it [ a proposal] - I could be waiting a long time."
Heidi was previously engaged to DJ and TV presenter Dave Berry, who she dated for eight years.
She was in three-piece girl group Sugababes for 11 years, but the band currently have "no plans" to reform.
Instead she is busy renovating her new house with Alex. They have bought an old warehouse in London and are doing it up.
Congratulations Heidi and Alex!
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