The unseeded Monegasque produced an impressive performance to overcome the American 7-6(5), 6-3 in the semi-finals, securing his place in a second ATP Tour-level final.
Vacherot will face Czech eighth seed Jiri Lehecka in Sunday's championship match after the latter recovered from a set down to defeat Germany's Jan-Lennard Struff 3-6, 7-5, 6-4.
Vacherot holds his nerve in opening-set tie-break
The opening set was closely contested, with both players demonstrating impressive serving and refusing to give their opponent an easy opportunity.
Fritz looked well placed to take control when he established a 5-3 advantage in the tie-break. However, Vacherot responded brilliantly, winning six of the next seven points to claim the tie-break 7-5 and take the opening set.
The Monegasque carried that momentum into the second set, maintaining pressure on Fritz's serve and creating opportunities to break.
Vacherot eventually secured the decisive break to move ahead 5-3 before holding his nerve to close out the match 6-3.
The victory took one hour and 27 minutes and ended Fritz's hopes of reaching another final this season.
Lehecka fights back to book final place
Vacherot's opponent in the final will be Jiri Lehecka, who produced a determined comeback against Jan-Lennard Struff.
The German took the opening set 6-3 and moved close to securing his place in the final.
However, Lehecka responded by winning the second set 7-5, saving a match point along the way, before completing the comeback with a 6-4 victory in the deciding set.
The Czech will now have an opportunity to claim his first title of the 2026 season after reaching several finals without lifting a trophy.
Vacherot targets second career title
The Basel final represents Vacherot's second ATP Tour-level championship match and his first since his historic triumph at the Shanghai Masters in October 2025.
His Shanghai success was particularly remarkable because he entered the tournament as a qualifier before defeating several highly ranked opponents to claim the biggest title of his career.
The 27-year-old will now aim to add another trophy to his collection and continue his impressive progress on the ATP Tour.
Previous meetings favour neither player
Vacherot and Lehecka have won one match apiece in their previous two meetings.
Lehecka won their most recent encounter in the semi-finals of the Tokyo tournament earlier in October, while Vacherot defeated the Czech at the Paris Masters in 2025.
Their Basel final therefore presents an opportunity for both players to take the lead in their head-to-head record.
Swiss Indoors Basel semi-final results:
• Valentin Vacherot: Defeated Taylor Fritz 7-6(5), 6-3.
• Jiri Lehecka: Defeated Jan-Lennard Struff 3-6, 7-5, 6-4.
Final: Valentin Vacherot vs Jiri Lehecka – Sunday, 1 November 2026.