It means Halep is the first player through to this weekend's final, where she will face the victor of Thursday's second semi-final between seven-time Wimbledon champion Serena Williams and unranked Czech Barbora Strycova.
But from there No. 7 seed Halep - already a grand slam champion at the 2018 French Open - raced into the lead, wrapping up the rest of first set in the same time it took to play those first two games.
Williams has served 45 aces on her way to the final and won three quarters of points on her first serve.
Strycova, who has hinted she could retire from the sport this year, is the underdog coming into the match but insists she has nothing to lose.
For one thing, she shouldn't focus too much on trying to raise her Grand Slam title total to 24, a number achieved by just one other player in tennis history.
The former world No 1, who booked a place in her first ever Wimbledon final by beating Elina Svitolina 6-1, 6-3 on Thursday, has close to 300,000 followers but only follows two accounts herself. Konta said Strycova's comeback was due to her good play and not mistakes that she committed.
"It feels wonderful. It is the first semi-final for me, and I actually didn't expect it to happen here", she said.
Sure, Serena. Just pretty good. "I can play everywhere, against anyone". Svitolina had the same fate to fall behind 2-0 in the first set.
A cross-court forehand passing shot delivered the break for Williams, and Strycova bent over again, one of the initial signs that she was dealing with something physical.
Among Strycova's arsenal is an effective serve-and-volley game, honed in a way that will be familiar to many who loved the tennis of previous generations of players.
Although Svitolina stayed with Halep for the first part of the second set, the self-belief and fight had gone and when the Romanian broke for 4-3 it was game over.
Williams, whose two sets win took her to 200 career sets won at Wimbledon joint second with Chris Evert in the all-time women's list behind Martina Navratilova (249), says that she is in a better frame of mind than she was when she ended up losing in both the Wimbledon and US Open finals a year ago.
But Williams, who will become the oldest woman in the professional era to contest a Grand Slam final on Saturday, is taking it all in her stride. "I knew she was going to hit with a lot of power, but I knew today I had to be as strong as possible".
Elina Svitolina is dejected after losing a point to Simona Halep.
Halep seemed headed for a long day when her semifinal against Svitolina began with a pair of games encompassing 32 points across 20 minutes. "I've had some big ones", said Williams, whose fastest delivery so far stands at 122 miles per hour.