Following Wolverhampton Wanderers' triumph over Southampton on Saturday, the Tractor Boys were the last team without a top-flight win on the board, but they capitalised on a lethargic display from Spurs to end a 22-year wait for their next Premier League success.
First-half strikes from Sammie Szmodics and Liam Delap proved telling for the visitors, who had to weather a Spurs storm in the second half after Rodrigo Bentancur pulled one back, but Tottenham's comeback powers failed them in another questionable display from Ange Postecoglou's men.
No doubt nursing at least a minor hangover from their unsuccessful Europa League exploits in Turkey, Tottenham unsurprisingly had the lion's share of the ball against their newly-promoted visitors, but their conviction in attack was lacking.
An apparent injury to Dominic Solanke did not help matters for the hosts, who were taught an attacking lesson by Kieran McKenna's men in the first half, where an acrobatic Szmodics effort preceded a close-range Delap finish.
Boos greeted the home side as they made their way off the field, but not a single soul was questioning Spurs' fightback prowess, as they had already beaten West Ham United, Brentford and Aston Villa at home this season after conceding the first goal.
Postecoglou's side briefly thought that their turnaround mission had lift-off at the start of the second half, only for Solanke's response to be chalked off by the VAR for handball, but the Lilywhites belatedly made things interesting through a Bentancur bullet header approaching the final 20.
However, Spurs' quest for an elusive second ended in failure against their Premier League bogey team, as a jubilant Ipswich made it four top-flight wins on the bounce versus Tottenham, who are now as low as 10th while McKenna's side jump out of the drop zone and into 17th place.
TOTTENHAM VS. IPSWICH HIGHLIGHTS
Sammie Szmodics goal vs. Tottenham (31st min, Tottenham 0-1 Ipswich)
A Sammie Szmodics special!
Tottenham fail to properly deal with Jens Cajuste's cross into the box, and Brennan Johnson pulls out of trying to head the ball away, seemingly noticing that Szmodics is winding up for a bicycle kick and acting in the interests of his own safety.
The Ipswich forward accepts the invitation to shoot and finds the bottom corner with a terrific overhead effort. Spurs fall behind at home again, but they have come back to win their last three on their own patch when conceding first!
Liam Delap goal vs. Tottenham (43rd min, Tottenham 0-2 Ipswich)
Tottenham's comeback job just got much more difficult!
It is a complete mess from the hosts, as Szmodics's cutback from the left byline deflects off of Guglielmo Vicario's glove and onto the shin of Radu Dragusin, who appears destined to score an own goal.
However, Delap pounces to make absolutely sure, smashing the ball into the roof of the net from a yard out to double the visitors' lead. PL win number one inbound?
Rodrigo Bentancur goal vs. Ipswich (69th min, Tottenham 1-2 Ipswich)
Strap in for a gripping finale!
Spurs finally cut the deficit in half with just over 20 minutes of normal time remaining, as Bentancur loses his marker at a corner and meets Pedro Porro's outswinging delivery with a powerful header high into the goal.
MAN OF THE MATCH - SAMMIE SZMODICS
Playing a huge role in both of Ipswich's goals on the day, Szmodics deserves all the plaudits for his terrific overhead kick for the Tractor Boys' opener, before it was his cutback that caused chaos between Vicario and Dragusin and put the ball on a plate for Delap.
Take nothing away from the performance of Arijanet Muric in between the posts too; the Tractor Boys number one made five big saves, including a crucial stop from Solanke right at the death to ensure his side would take home maximum points.
TOTTENHAM VS. IPSWICH MATCH STATS
Possession: Tottenham 67%-33% Ipswich
Shots: Tottenham 17-8 Ipswich
Shots on target: Tottenham 5-3 Ipswich
Corners: Tottenham 12-2 Ipswich
Fouls: Tottenham 10-19 Ipswich
BEST STATS
WHAT NEXT?
Once the final international break of the season is out of the way, Tottenham ought to view their trip to Manchester City on November 23 as a prime opportunity to bounce back, given their penchant for positive results against the champions and the Citizens' current struggles.
Coincidentally, Ipswich's next match comes against City's formerly noisy neighbours, as they host Manchester United on November 24 in the Red Devils' first match under Ruben Amorim.