| Challenger Segovia | 07/27 08:00 | 25 | [269] Mirza Basic v Matteo Viola [264] | 4-6,1-6 | |
| Challenger Pozoblanco | 07/22 17:20 | 26 | [262] Matteo Viola v Emilio Nava [435] | 5-7,6-4,3-6 | |
| Challenger Pozoblanco | 07/20 17:10 | 25 | [262] Matteo Viola v Thomaz Bellucci [322] | 6-1,6-3 | |
| Challenger Todi | 07/13 19:35 | 25 | [166] Tomas Martin Etcheverry v Matteo Viola [260] | 6-4,7-6 | |
| Challenger Salzburg | 07/06 09:00 | 25 | [260] Matteo Viola v Carlos Taberner [113] | 4-6,4-6 | |
| Challenger Porto | 06/30 13:45 | 26 | [260] Matteo Viola v Sergiy Stakhovsky [242] | 2-6,6-4,5-7 | |
| Challenger Porto | 06/28 12:00 | 25 | [252] Roberto Cid Subervi v Matteo Viola [260] | Retired | |
| ATP Mallorca | 06/19 16:30 | 14 | [251] Matteo Viola v Joao Sousa [109] | 4-6,4-6 | |
| Challenger Aix en Provence | 06/15 16:25 | 25 | [182] Elias Ymer v Matteo Viola [251] | 6-4,7-6 | |
| Challenger Nottingham | 06/06 18:30 | 14 | [313] Igor Sijsling v Matteo Viola [251] | 6-7,6-1,6-0 | |
| ATP Parma | 05/23 12:55 | 19 | [101] Mikael Ymer v Matteo Viola [249] | 6-4,3-6,6-0 | |
| ATP Parma | 05/22 12:50 | 14 | Evgeny Karlovskiy v Matteo Viola | 5-7,7-5,5-7 | |
| Challenger Biella | 05/17 14:55 | 25 | [249] Matteo Viola v Alexandre Muller [189] | 6-4,3-6,1-6 | |
| Challenger Zagreb | 05/09 11:10 | 14 | [183] Emilio Gomez v Matteo Viola [252] | 7-5,6-7,6-1 | |
| Challenger Biella | 05/03 08:30 | 19 | [220] Maximilian Marterer v Matteo Viola [252] | 6-3,7-5 | |
| Challenger Biella | 05/02 10:00 | 14 | [253] Matteo Viola v Elliot Benchetrit [245] | Retired | |
| Challenger Rome | 04/18 13:25 | 14 | [249] Matteo Viola v Alexey Vatutin [270] | 3-6,7-6,1-6 | |
| Challenger Split | 04/12 08:30 | 19 | [225] Zdenek Kolar v Matteo Viola [249] | 6-2,6-4 | |
| Challenger Split Qual | 04/11 09:00 | 14 | Evgeny Karlovskiy v Matteo Viola | 2-6,2-6 | |
| ATP Cagliari | 04/05 10:30 | 19 | [128] Jozef Kovalik v Matteo Viola [251] | 7-6,4-6,7-6 | |
| ATP Cagliari | 04/04 09:45 | 14 | [249] Matteo Viola v Brandon Nakashima [143] | 6-7,6-1,6-2 | |
| ATP Miami | 03/23 18:10 | 19 | [249] Matteo Viola v Mischa Zverev [280] | 7-6,4-6,1-6 | |
| ATP Miami | 03/22 20:20 | 14 | [146] Bernabe Zapata Miralles v Matteo Viola [249] | 6-7,2-6 | |
| ATP Singapore | 02/21 05:25 | 19 | [225] Matteo Viola v Altug Celikbilek [299] | 2-6,6-0,6-7 | |
| ATP Singapore | 02/20 07:20 | 14 | [225] Matteo Viola v Alex Lawson [124] | 6-3,6-2 | |
| Challenger Biella | 02/16 11:35 | 25 | [225] Matteo Viola v Andreas Seppi [108] | 2-6,6-4,5-7 | |
| Challenger Biella | 02/15 11:30 | 19 | [225] Matteo Viola v Hiroki Moriya [242] | 6-0,6-1 | |
| Challenger Biella Qual | 02/14 12:20 | 14 | [225] Matteo Viola v Andrea Arnaboldi [273] | 2-6,6-2,6-3 | |
| Challenger Biella | 02/10 17:55 | 26 | [225] Matteo Viola v Blaz Rola [159] | 6-3,5-7,4-6 | |
| Challenger Biella | 02/08 14:25 | 25 | [257] Blaz Kavcic v Matteo Viola [225] | 3-6,6-3,5-7 |