Alexis Sanchez scored the opener before the Argentine doubled the scoreline and, though the visitors pegged a goal back, the skipper and Xavi finished them off.
Alexis Sanchez gave Barca the lead before Lionel Messi netted his 229th La Liga goal with an inch-perfect free kick, a strike that saw the Argentinian overtake Real legend Raul to become the third-highest Liga scorer in history. Angel Trujillo unexpectedly pulled one back for Almeria, but goals from Carles Puyol and Xavi completed the rout.
Gerardo Martino made six changes to the side that lost 3-1 to Real Sociedad last week, with Andres Iniesta being the most high-profile player to lose his place.
Barca looked destined to put that disappointment behind it from the outset, with Sanchez opening the scoring after just nine minutes by converting the rebound after Esteban failed to hold Cesc Fabregas' effort.
Almeria's task became even more daunting on 25 minutes, as Messi expertly curled an unstoppable free kick into the top-left corner from 25 yards to claim yet another goalscoring milestone.
However, Almeria earned itself an unlikely lifeline just two minutes later, when Miguel Angel Corona's inviting corner was headed past the stranded Victor Valdes by defender Trujillo.
Messi almost restored Barca’s two-goal cushion late in the first half, but he nodded just wide after beating Esteban to a loose ball in the area.
The hosts made a sluggish start to the second half, but that did not stop Xavi creating a great opportunity for Neymar as he fed the Brazilian into the left side of the area, only for the forward to shoot straight at Esteban.
Valdes then had to bail Barca out just after the hour, as Aleix Vidal inexplicably found space in the home side's area before letting fly with a powerful left-footed effort that went right at the keeper.
Neymar wasted another big chance shortly after as he opened his body up and shot well wide of the far post from close range.
But Barca finally put breathing space between itself and Francisco's men seven minutes from time as Puyol knocked in after Messi's towering header had hit the bar, before Xavi stroked an excellent finish beyond Esteban from 20 yards.