Wanderers only had to match whatever the Hammers did to stay up, but when they raced into a two-goal lead after 21 minutes it looked all over.
Yet the former Wanderers striker Michael Ricketts had them sweating when he pulled a goal back in the second half, but the Trotters managed to hang on to stay in the top division for a third consecutive year, the first time in over 40 years they had done that.
Bolton set their sights on breaching the Middlesbrough defence from the start with Bernard Mendy only inches wide of the far post with a third minute shot.
That was quickly followed by another quick opening, this time created by the trickery of Jay-Jay Okocha, that ended with Henrik Pedersen only just failing to hit the target.
On ten minutes came the breakthrough that Wanderers wanted and it all stemmed from a disputed throw-in.
Wanderers claimed that it was theirs, the referee gave it the other way but when the ball was played to Jonathan Greening, he was robbed by Per Frandsen, who then raced at the Boro goal before unleashing a 25-yard thunderbolt that flew into the corner of the net.
That took the immediate pressure off the home side but Middlesbrough began to enjoy some possession, but they found the Wanderers back four in equally determined mood.
Even so it was the home side's attack that looked to be the early heroes and when Wanderers were awarded a free-kick just outside the area, Okocha stepped up to curl an unstoppable effort past the despairing dive of Mark Schwarzer.
It all looked to be going to plan for the home side, but they had to be alert to possible danger when Malcolm Christie found possession just outside the six-yard box, but Ricardo Gardner blocked Boro's best chance of the half with a perfectly-timed tackle.
The only blemish on the Wanderers performance up to the halfway stage were needless bookings for Frandsen and Mendy.
If Wanderers thought the second half was going to be easy they were quickly put in their place by their former striker Ricketts.
He warned his old side with a couple of headers that narrowly missed the target before he netted in in the 62nd minute.
Then there was the news from St Andrew's that West Ham had gone in front of Birmingham and that seemed to send the home team into a panic.
Their play suddenly became nervous to a point of suicidal defending and it was only a red card for Middlesbrough full-back Franck Queudrue for a high tackle on Ivan Campo that settled them down.
Even so it was a tense finish, but Birmingham's fightback finally ensured Wanderers' place in next season's Premiership.