Veteran marksman Phillips, 34, in his 50th appearance for Albion, helped himself to a first-half double either side of a strike from 20-year-old rookie Miller.
Robert Koren was on target in the 57th minute with Jonathan Greening grabbing the fifth eight minutes later as Albion raced to their biggest win of the season.
Phillips has now scored six goals in seven games with on-loan Manchester City marksman Miller on target five times in seven matches.
Rangers, who briefly gave themselves hope when they were trailing 2-0 through Gareth Ainsworth's first goal of the season, simply had no answer to the skill of Phillips and the pace and power of Miller.
This latest defeat, their fourth in seven league games, leaves them rooted to the bottom of the table and still searching for their first win of the season after collecting just three points from a possible 21.
It has also put more pressure on manager John Gregory who could only stand and watch as Albion extended their 100 per cent home record in the league with a fourth straight win.
Rangers fate was effectively sealed when the Phillips and Miller combined to fire Albion 2-0 ahead in the space of 60 seconds.
Miller powered past full-back Zesh Rehman in the 17th minute and crossed for Phillips, who had earlier hit the post, to score from just three yards.
Phillips repaid Miller a minute later with a defence-splitting pass. Miller surged away from Damion Stewart before beating goalkeeper Lee Camp with low drive.
It looked set to be the signal for Albion to take total control. But battling Rangers secured a lifeline in the 24th minute when Ainsworth found himself unmarked at the far post.
He had the simple task of stabbing the ball into an empty net after he had been picked out by a header from Dexter Blackstock.
Unfortunately for Rangers it proved to be a false dawn as Albion then laid siege to their goal.
James Morrison was denied by Camp and Stefan Moore cleared off the line from Leon Barnett before Albion's pressure finally paid a dividend in the 39th minute.
After Camp had punched clear a shot from Miller, Greening collected the loose ball and picked out Phillips on the edge of the area.
There seemed to be no danger for Rangers, but Phillips spotted that Camp was marginally off his line and chipped the ball over his head and into the far corner of the net.
Phillips came close to grabbing his hat-trick in the 57th minute only to be denied by Camp.
But Camp's saved deflected the ball into the path of Koren who volleyed home from the edge of the area.
Greening then set the seal on a powerful Albion display after 65 minutes.
Chris Brunt's corner was headed clear by Blackstock, but it fell invitingly for Greening who let fly from 25 yards.