Christopher Schindler scored his first Huddersfield Town goal to keep David Wagner's side top of the Championship.
The £1.8m record signing from 1860 Munich headed home from Aaron Mooy's 59th-minute corner to seal his side's eighth win of the season and third away from home.
The German centre-back was later forced off with a facial injury, but Town still claimed another three points to go into the international break with 25 from a possible 33.
Wagner's hard-working side hit a post through Elias Kachunga in the first half and were good value for their victory against a home side who have now failed to score in four successive games.
There were 803 visiting supporters in a 16,146 crowd to see only a third Town win in 22 visits to Portman Road.
WATCH: Examiner Duo Doug Thomson and Blake Welton preview Huddersfield Town's trip to Ipswich Town
First Half
6 mins:Jonathan Hogg's header from Chris Lowe's corner is saved by home keeper Bartosz Bialkowski.
15 mins:Sean Scannell's foul on Josh Emmanuel brings Ipswich a central free-kick 25 yards out but Tom Lawrence puts it just wide.
20 mins: Jonas Knudsen's foul on Tommy Smith brings Town a free-kick taken by Aaron Mooy but its cleared.
22 mins: Leon Best breaks clear but he is adjudged to be offside.
28 mins: After Nahki Wells and Mooy combine, Elias Kachunga shoots against the right-hand post - Wells tries his luck from the rebound but Bialkowski saves.
35 mins: Knudsen shoots over after being teed up from a free-kick.
39 mins: Luke Chambers' close-range header is blocked by Christopher Schindler.
42 mins: Best's flick-on finds Grant Ward in space but he lofts his effort off target.
WATCH: Doug Thomson and Blake Welton on Ipswich v Huddersfield Town at Half Time
Second Half
53 mins: Smith's shot is deflected over the bar.
59 mins: Town go ahead through Christopher Schindler, who heads home a Mooy corner.
62 mins: Sean Scannell's deflected effort is held.
66 mins: Freddie Sears shoots, Town's Danny Ward saves.
81 mins: Ward smothers the ball after a Hogg slip inside the penalty area.
90+1 mins: Luke Varney drills a shot well over.
90+6 mins: Ipswich force successive corners, but Town survive.
WATCH: Huddersfield Town players celebrate with the fans after sealing a 1-0 win over Ipswich Town
Teams
Ipswich: Bialkowski, Emmanuel, Chambers, Berra, Knudsen, Douglas, Skuse, Ward (Bishop, 57), Bru (Sears, 57), Lawrence (Varney, 86), Best.
Subs not used: Digby, Grant, Wenlock, Gerken.
Town: Ward, Smith, Hudson, Schindler (Hefele, 70), Lowe, Hogg, Whitehead (Van La Parra, HT), Scannell (Cranie, 87), Mooy, Kachunga, Wells.
Subs not used: Holmes-Dennis, Payne, Palmer, Coleman.
Referee: Chris Kavanagh (Manchester).