| # | Swimmer | Team | Seed | Time | Diff |
| 1 |
Balade, Nahuel A (10)
|
FGCM |
39.43 |
37.82 |
-1.61 |
| 2 |
Lopez-Casula, Leonardo (10)
|
FGHSC |
41.04 |
38.98 |
-2.06 |
| 3 |
Fernandez-Chung, Lucas (9)
|
FGASC |
40.51 |
39.00 |
-1.51 |
| 13 |
Longo, Kai (9)
|
FGEA |
44.38 |
42.09 |
-2.29 |
| 21 |
Bahniuk, Matthew H (9)
|
FGGRSC |
46.37 |
43.81 |
-2.56 |
| 24 |
Tapias, Ethan (10)
|
FGFFSC |
51.80 |
47.13 |
-4.67 |
| 28 |
Morales, Andres I (10)
|
FGGRSC |
51.01 |
48.79 |
-2.22 |
| 31 |
Frable, Rafael M (10)
|
FGAKS |
48.50 |
49.67 |
1.17 |
| 32 |
Negrin, Axel (8)
|
FGFFSC |
49.32 |
49.76 |
0.44 |
| 33 |
Warrington, Daniel (10)
|
FGFKSC |
51.09 |
50.41 |
-0.68 |
| 36 |
Vega, Braison (8)
|
FGASC |
1:00.92 |
51.88 |
-9.04 |
| 37 |
Tully, Vincent R (9)
|
FGGRSC |
48.52 |
52.42 |
3.90 |
| 43 |
Sosa, Santiago N (7)
|
FGGRSC |
52.38 |
56.92 |
4.54 |
| 44 |
Alvarado, Kendy A (10)
|
FGCM |
54.84 |
59.19 |
4.35 |
| 46 |
McPeek, Logan (9)
|
FGAKS |
57.33 |
1:00.06 |
2.73 |
|
Fernandez, Luca V (9)
|
FGEA |
|
DQ |
- |
|
Akl, Lucas I (8)
|
FGGRSC |
|
DQ |
- |
|
Munoz, Federico (7)
|
FGASC |
|
DQ |
- |
|
Caraballo, Nicolas E (8)
|
FGGRSC |
57.12 |
NS |
- |