Reade and Phillips both went fastest in qualifying for the time trial event at the National BMX Centre then maintained their position in the Superfinal field of 16.
Reade clocked a time of 32.351 seconds to win by almost a second ahead of America's Alise Post while Phillips posted 29.357 to edge out Canadian Tory Nyhaug.
Both Brits will now tackle the motos event in Manchester and Reade, who finished sixth at the London 2012 Olympics, is looking for more of the same from the time trials.
"It was good just to win. It's my home track so I know it pretty well," said Reade. "They put the ramp in there so that spiced things up a bit, but I'm really pleased to piece it all together and do a solid lap to finish with.
"If we get the right process, generally the result takes care of itself. If I can perform that lap every time in the motos, through the semi and the final, hopefully I'll be on top of that podium."
And Phillips, who joined Reade at the London 2012 Olympics last summer, finishing eighth, is determined to also follow up his performance in the time trail with success in the motos.
"I've never won a time trial. I've come close a couple of times and thought I was going to win at the worlds but it was not to be," said Phillips.
"Ultimately, I feel a bit weird about it because it's just a form of qualification. At the World Championships it's slightly different because there's a rainbow jersey on the line.
"So that's one you really, really want to win. These are ultimately just qualification, but it's always nice to start off the weekend.
"On paper, I've got a really good chance, but you've got seven other guys up there side by side. All it takes is for you to go a fraction of a second late out of the gate, or go a bit early, or make a mistake, and it's all over.
"So we'll just go through the motions and see where we're at."
- Sports & Recreation