Jordan Smotherman’s winner made the difference as the Giants took home the season’s first piece of major silverware, retaining the trophy they won last year.
Giants coach Adam Keefe says his team perhaps weren’t at their best, but did enough to secure his second honour in charge at the club.
He told BBC Sport Northern Ireland: “I don’t think we had the legs that we normally do, but our experience shined through and we got the job done.
“We knew they were going to come, I remember us last year in this one-off championship game and the way we came out against Cardiff Devils.
“We were the underdogs for that one, some would say and we knew Guildford would have some push going into it. They’re a team that skates well with some good talent in there and we needed to nullify that as best we could.”
Guildford counterpart Paul Dixon was a proud man, despite seeing his team come up short in their first Elite League cup final.
And he admits it’s a difficult feeling to process after taking the Giants all the way to the extra period, only to lose out in the end.
“We have a group of guys who are absolutely devastated to be so close, yet fall just short,” he said.
“We gave everything we had, and we had our chances to be the winner but it just wasn’t to be, and it is difficult for all of us to process the emotion that comes with that.”
“There is no need for anyone here to hang their heads, and hopefully all of us can remember all the success we had to get this far and not let one goal in overtime take away from what has been a great achievement for this club.”
“We will take a couple of days to get over the outcome and then get back to looking at league play and going for a run into the playoffs.”