After losing only one of their previous four league games, Newcastle were always favourites for victory against the division's bottom club, and their hopes were boosted by a first half in which they hit the post twice and Huddersfield's Tommy Smith was sent off.
Huddersfield clung on to reach the interval on level terms despite Smith's poor challenge on record signing Almiron, whose excellent performance was eventually rewarded as Newcastle cruised to victory in the second half.
Salomon Rondon broke the deadlock in the first minute of the second half and Ayoze Perez quickly made it 2-0, moving Newcastle up to 14th. Huddersfield remain 14 points adrift of safety and appear certain to be relegated.
A wonderful counter-attack almost saw Almiron claim a goal early on, his dinked finish over Jonas Lossl striking the left-hand post, which Rondon then rattled on the follow up.
Rondon was denied by the brilliant Lossl and the Terriers' task was made harder when Smith rightly saw red for a rash diving tackle on Almiron.
Lossl sprung to his right to keep out a low Almiron strike, but almost gifted him a goal as a tame effort squrimed under the Dane and had to be cleared by Chris Lowe.
Perez became the latest to draw a fine save from Lossl before Rondon spurned a gilt-edged chance just before half-time, somehow diverting Sean Longstaff's superb right-wing cross well wide.
However, the dam finally broke 59 seconds into the second half, DeAndre Yedlin controlling Florian Lejeune's cross-field ball and playing in Perez, who combined with Isaac Hayden to tee up Rondon to fire through Lossl's legs.
Just over five minutes later the points were effectively sealed as Yedlin and Rondon combined following Almiron's pass and Perez volleyed into the bottom-left corner.
Only the crossbar prevented Newcastle from adding to their lead, Kenedy and Longstaff each striking it in the closing stages.
What does it mean? Newcastle make most of favourable fixture
While it may be unfair to consider a home game against Huddersfield straightforward given their exploits last season, this is a very different team to the one that stayed up under David Wagner and Newcastle made sure not to fluff their lines with a superb attacking performance. They were relentless after Smith was dismissed and the margin of victory could have been much greater.
Almiron injects life into Newcastle attack
Newcastle have been able to get results under Rafael Benitez, but this was the best their attack has looked all season and new boy Almiron was the key. His range of passing and link-up play injected life into a forward line that looked quicker and more fluid for his presence. The standing ovation he received after being substituted late on was richly deserved.
Smith's rush of blood costs Terriers
Smith did his best to protest his innocence but he could have no complaints about his red card, which significantly diminished Huddersfield's hopes of an upset.
Key Opta Facts
46 - Salomón Rondón has been directly involved in 46% of Newcastle's 24 Premier League goals this season (7 goals, 4 assists). Spearhead.— OptaJoe (@OptaJoe) February 23, 2019
- Newcastle have done the league double over Huddersfield for the first time since 1964-65.
- Only two sides in Premier League history have picked up fewer points after their first 27 games of a season than Huddersfield in 18-19 (11) - Derby in 07-08 (9) and Sunderland in 05-06 (10).
- Newcastle mustered 29 shots, their most in a Premier League game since attempting 32 against Swansea City in November 2012.
- Huddersfield’s Jan Siewert is the ninth manager to lose his opening four Premier League matches in charge, and the first since Frank de Boer with Crystal Palace at the start of last season.
- No side has picked up more red cards in the Premier League this season than Huddersfield (4, along with Everton and Leicester).