The two Ferrari drivers ended up third and fourth with Carlos Sainz ahead, while Charles Leclerc made a small error on his final Q3 lap that proved costly in the fight for pole.
The session was delayed by 35 minutes due to rain dousing the Spa track yet again this weekend, with the precipitation falling particularly hard in the hour ahead of the shootout qualifying.
In Q3, Lewis Hamilton led after the first runs, where some drivers, including Sergio Perez, took an alternative approach of putting in an extra preparation lap.
The Mexican, therefore, headed the times before being shuffled back to eighth, while Hamilton ended up improving only enough for seventh on his second flier after an apparent miscommunication with his team-mate George Russell meant the Mercedes appeared to get in each other's way going up the Eau Rouge/Raidillon sequence up to the Les Combes chicane.
Leclerc was well in the hunt for pole as he set the quickest times in sectors one and three on his second Q3 softs flier, but a slip that nearly had him off the road at Turn 9 cost him so much time he ended up unable to beat Sainz's 1m49.081s that was good enough for third.
Both were then beaten by a late stunner from Piastri that featured the best time in the middle sector, before the McLaren driver was beaten by Verstappen completing the final flying lap of all in the session that sets the grid for Saturday's sprint race.
Although the Dutchman registered no purple sectors on his final lap, he still had enough consistency to post the best time of all at 1m49.056s.
Lando Norris took sixth in the other McLaren ahead of Alpine's Pierre Gasly, who also deployed the double warm-up tour approach in Q3.
Esteban Ocon was ninth ahead of Russell, who had also scraped through Q1 and Q2 on the edge of elimination in 15th and 10th in the opening segment.
The Briton's mistake at La Source on his final Q3 run – he locked up and ran deep – left him running ahead of Hamilton and the rest of the incident that appeared to cost the seven-time world champion a better shot on his own last effort.
Before this, Q2 was building towards its conclusion when attention turned to Lance Stroll being the first driver to attempt to slicks – the Canadian pitting to change his inters for mediums.
He was 0.8s down on Verstappen's segment-topping time by the end of the first sector, where most of the track did have a dry line, but when he arrived at the still-wet Turns 8 and 9, it all went wrong.
Despite being very cautious on his approach to Turn 9, Stroll lost the rear of his Aston and slid across the gravel into the barriers, knocking off his right-front wheel.
The red flags then flew and prevented any improvement, which eliminated early Q2 leader Daniel Ricciardo and the Williams pair Alex Albon and Logan Sargeant, who spun coming out of the second part of Stavelot a few minutes before Stroll's crash, in 11th, 12th and 13th.
Neither Williams pair set a time, with Albon being credited ahead because of his position ahead of Sargeant on what was set to be his sole timed tour, while he was caught out by Stroll's crash having remained in the garage for most of Q2.
Albon, and Fernando Alonso in the other Aston, were finally on out-laps on their mediums having waited a long time seemingly in an effort to discover if a slicks attempt was possible, when the incident occurred and so they were knocked out too.
Stroll pitting meant he also lacked a timed lap on the inters, but he ended up ahead of his frustrated birthday-celebrating team-mate again by dint of his starting his flying lap on the mediums while Alonso was still on his out-lap.
In Q1, which Verstappen topped as the times fell over four seconds from Hamilton's initial 2m02.297s, Yuki Tsunoda set a personal best on his final effort but could not do better than 16th with many others finding time behind the AlphaTauri.
Valtteri Bottas was not one of these as he finished his final flier well ahead of the dash for the flag, with the Alfa Romeo driver heading for the pits as his rivals ended the opening segment and he only registered 17th.
Kevin Magnussen was the lead Haas driver in a very different session for the American team, with the Dane and team-mate Nico Hulkenberg bucking the trend of circulating throughout the 12-minute segment and twice pitting for fresh inters.
This meant neither had a time on the board ahead of the final laps and with Hulkenberg delayed a few seconds leaving the pits for the third time by a jack being left near his car following his second inters change, he ran out of time and did not even get to attempt a flier.
That left Hulkenberg last behind Zhou Guanyu in the other Alfa Romeo, but Magnussen could only manage 18th just ahead of that pair with his sole time lap, despite completing the same number of tours in Q1, 7, as Verstappen.
Q1 also featured an incident where Verstappen had to go along away around Hamilton going slower on the racing line being noted for a possible impeding infraction, but the stewards decided no further action was necessary.
| Cla | Driver | Car / Engine | Time | Gap |
| 1 | Max Verstappen | Red Bull/Honda RBPT | 1'49.056 | |
| 2 | Oscar Piastri | McLaren/Mercedes | 1'49.067 | 0.011 |
| 3 | Carlos Sainz | Ferrari | 1'49.081 | 0.025 |
| 4 | Charles Leclerc | Ferrari | 1'49.251 | 0.195 |
| 5 | Lando Norris | McLaren/Mercedes | 1'49.389 | 0.333 |
| 6 | Pierre Gasly | Alpine/Renault | 1'49.700 | 0.644 |
| 7 | Lewis Hamilton | Mercedes | 1'49.900 | 0.844 |
| 8 | Sergio Perez | Red Bull/Honda RBPT | 1'49.961 | 0.905 |
| 9 | Esteban Ocon | Alpine/Renault | 1'50.494 | 1.438 |
| 10 | George Russell | Mercedes | 1'55.742 | 6.686 |
| 11 | Daniel Ricciardo | AlphaTauri/Honda RBPT | 1'57.687 | 8.631 |
| 12 | Alexander Albon | Williams/Mercedes | - | - |
| 13 | Logan Sargeant | Williams/Mercedes | - | - |
| 14 | Lance Stroll | Aston Martin/Mercedes | - | - |
| 15 | Fernando Alonso | Aston Martin/Mercedes | - | - |
| 16 | Yuki Tsunoda | AlphaTauri/Honda RBPT | 2'00.568 | 11.512 |
| 17 | Valtteri Bottas | Alfa Romeo/Ferrari | 2'00.951 | 11.895 |
| 18 | Kevin Magnussen | Haas/Ferrari | 2'01.079 | 12.023 |
| 19 | Zhou Guanyu | Alfa Romeo/Ferrari | 2'01.430 | 12.374 |
| 20 | Nico Hulkenberg | Haas/Ferrari | - | - |
