The couple has been dating since they shot the pilot for the vampire show in the summer of 2007.
Paquin was forced to dismiss recent reports that she was set to walk down the aisle with Moyer, insisting the claims were "not true."
But the happy couple is now forging ahead with wedding plans -- representatives for both stars have confirmed they are engaged.
No further details were available as WENN went to press.
Moyer has two children from previous relationships -- son, Billy, born in 2000, and a daughter, Lilac, born in 2002.
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