"It worked out, so we're not going to be too mad," said Kyle Korver, who scored 13. "We had a bunch of these that have gone the other way."
Wade had 28 points, 11 rebounds and nine assists for the Heat. He sent the game into overtime after sinking two of three free throws with 2.1 seconds left in regulation. Udonis Haslem scored 15 points and had 10 rebounds, and Antoine Walker had 19 points and 12 rebounds.
Willie Green added 16 points and Samuel Dalembert 15 for the Sixers, who snapped a three-game losing streak and nearly gave this win away after rallying in the fourth.
Miller, who put the Sixers ahead 87-85 on a jumper with 28 seconds left in the fourth, foolishly fouled Wade on a 3-point attempt in the final seconds. Wade, an 82 percent free-throw shooter, missed the first foul shot and sank the next two to send the game into overtime tied at 89.
"It was in an out. There was nothing I could do about it," Wade said of his miss. "I shot it just like the others. It was just one of those games."
Playing on the road a night after playing at home, the Heat ran out of steam in OT.
After Wade hit a nice step-back jumper to open overtime and give the Heat a 91-89 lead, the Sixers took control, and went 7-for-8 from the line in the extra frame.
The one field goal was an eye-popper, though. Iguodala stole the ball, took a quick glance at Walker, then threw down an emphatic breakaway dunk for a 92-91 lead that jolted the crowd.
Miami outrebounded Philly by 19, including a 23-3 edge on offensive boards. That helped the Heat outscore the Sixers 24-3 in second-chance points. Still, the Sixers made more plays down the stretch to stun the Heat the day after they beat Indiana, and Wade was only 10-for-26 from the field with five turnovers.
"We know why we lost and we need to move on," Wade said.
Wade's free throws in clutch were swift retribution after his turnover set up Miller's go-ahead shot. Needing one assist for a triple-double, Wade drove the lane and passed the ball out of bounds with 43 seconds left in the fourth.
Iguodala threw a bounce pass to Miller, who dribbled once to his right and buried the 13-footer as the crowd erupted. Green hit two free throws for a four-point lead, 89-85.
Wade scored on a layup to make it 89-87 and the inbounds pass deflected off Korver, giving the Heat one final shot. Wade fired the 3 from the left side and Miller seemed to get him on the elbow for the foul.
The Heat played without Shaquille O'Neal for the 32rd straight game while he recovers from knee surgery. He is day-to-day and interim coach Ron Rothstein said O'Neal could play Sunday against Dallas.
"We should be upset with ourselves that we put ourselves in that position," Rothstein said. "You could have all the excuses in the world when you end up with a loss. What good are excuses?"
Maybe Shaq can spark the Heat.
Off to a sluggish start, the Heat were quiet on the bench and trailed 63-46 late in the third. But these are the Sixers, and no lead is ever safe for the worst team in the East.
Walker hit a pair of 3-pointers and the Heat closed the third on a 20-7 run that pulled them to 67-63.
Philadelphia shot 56 percent in the first half and showed rare offensive balance, sinking seven straight shots at one point to open a 47-34 lead at halftime.
The Sixers got their first 3 from Green with 8:31 left in the third for a 56-42 lead. When Miller scored on driving layup, the Sixers were up 60-43 and where cheered going into a timeout.
Then they collapsed until pulling themselves together in the fourth.
"We're young, we're learning, it's been a bumpy road, but we are learning and we showed that tonight," Korver said.
Steven Hunter started at PF for the Sixers instead of Joe Smith. ... The Heat had scored 100-plus points in five straight games. ... The first game that O'Neal missed this season came in Miami's last visit to Philadelphia on Nov. 5.