Needing a draw to qualify for the last eight and a victory to win Group C, Angeldahl was at the centre of things as Sweden made no mistake.
The 25-year-old scored the first two goals, both in the first half, after a frustrating opening period for the side officially ranked the second best in the world.
An own goal from Portugal's Carole Costa moments before the half-time whistle made it three before a penalty from former City player Kosovare Asllani and a stunning goal from Arsenal's Stina Blackstenius completed the victory.
Sweden will now face one of Iceland, Belgium or Italy in Friday night's quarter-final. They will discover their opponents when Group D is concluded on Monday evening.
Angeldahl broke the deadlock in the 21st minute when she was the quickest to react after Portugal goalkeeper Patricia Morais dropped a corner.
City's midfielder reached the loose ball on the bounce and poked through the crowd and into the net.
It was another set piece that brought her second goal in the 44th minute.
This time, she stepped on to a wide free kick that was rolled into her path and curled it into the bottom corner from around 15 yards.
HT: Sweden 3-0 Portugal— BBC Sport (@BBCSport) July 17, 2022
THREE set piece goals give the favourites a commanding lead.
Filippa Angeldahl provided the finish for the second, a well worked training ground move 👇 🎯
📲💻📺 Watch and follow on @BBCiPlayer & the BBC Sport app#BBCFootball #BBCEuros #WEuro2022
That was the end of her direct goal involvement, although she continued to be key figure as part of the pressure that Sweden exerted on their counterparts.
It was that pressure that contributed to both the own goal and penalty, awarded for a handball just inside the box, that made the game safe.
With the victory certain, Angeldahl was eventually replaced in the 70th minute by Everton's Hanna Bennison.
Despite Netherlands' 4-1 win over Switzerland at Bramall Lane, Sweden's superior goal difference was enough to see them crowned as the winners of Group C.