The Glaswegian lost two finals in 2012 but took his chance in Newport to claim the £50,000 top prize - but Bingham will regret missing a golden chance to go 8-5 up.
The Englishman looked the calmer player at the start of the evening session, cutting a red gently to the corner pocket before working his way around the table for a 73 break that ended on the pink.
Maguire levelled at 5-5 with a brilliant 71 clearance after Bingham gave him a second chance at the table, but Bingham was clearly the player in form as he responded with a 118 clearance to re-take the lead in style.
He continued potting in frame 12 before missing a blue to right middle when splitting the pack, only to be reprieved when Maguire failed to slip the black between the right cushion and a red, having ignored the pink.
Bingham closed out the frame at the second attempt for a 7-5 lead heading into the interval. Maguire, sat with his head in his hands, welcomed the chance of 15 minutes to clear his head.
He re-emerged determined to take his chances. A dogged break ended with 35 points on the board as he failed to cut a red thinly enough; Bingham came back to 35-34 before leaving the table, and an almighty battle ensued.
When they reached the colours things became messy, with both players missing chances; Bingham enjoyed perhaps the best luck he will ever have in a frame - the white stopping right in the jaws at a key moment the highlight - then, after some quality defensive play from both cuemen with the Essex player 45-38 ahead, he doubled a shot-to-nothing blue to all but secure the frame.
With the pink seemingly easy to the same middle-left pocket, he contrived to miss - and Maguire potted pink and black to take an improbable frame and avoid going 8-5 behind.
Maguire was 39 points down in the next frame when Bingham opened the reds before missing. The pressure told as the Scot failed to make his rival pay - but Bingham was also starting to be affected by the tension, missing a straightforward red to bottom right to let Maguire back in immediately.
He went on to make 42, missing the pink, to level at 7-7.
Frame 15 was relatively straightforward, Maguire taking it with a 77, before a re-rack in the one following after another tense stand-off.
An early chance for Maguire to finish the match went begging following a massive kick on a red. A second chance was wasted as he closed on frame ball - a straightforward red stubbornly staying out this time - then he played a thoughtless safety, little more than hit and hope, to give Bingham yet another chance to save the match.
This time the world number 10 - by the rankings list of the week just ended, anyway - kept his composure to clear the table, potting blue for 59-59 before slipping pink and black into the centre of the recipient pockets.
Both players got on the board early in the decider, with Bingham fortunate to see the white not go in-off into left middle - but soon after, following a couple of safety shots, the cue ball dropped into that very pocket following another red from the Basildon potter.
A red sprung out of the pocket for Maguire but Bingham - renowned in recent times for playing well under pressure - again could not take his chance at a key moment.
Maguire would not make another mistake - although he almost left himself short on a red at 46-5, just sneaking past the pink to pot it - and potted frame ball pink before coaxing a red along the bottom cushion and pumping his fist in celebration.
He said he expects his hand to smart in the morning - his head probably will too, but he will not mind a bit after ending one of the most puzzling droughts in snooker.