| St. Lawrence Seaway Lighted Buoy 40 | Buoy | Fl R 4s | — | Cornwall 11 km |
| St. Lawrence Seaway Lighted Buoy 46A | Buoy | Fl R 4s | — | Cornwall 16 km |
| St. Lawrence Seaway Lighted Buoy 48A | Buoy | Fl R 4s | — | Cornwall 17 km |
| St. Lawrence Seaway Lighted Buoy 49 | Buoy | Fl G 4s | — | Cornwall 17 km |
| St. Lawrence Seaway Lighted Buoy 5 | Buoy | Fl G 4s | — | Cornwall 5 km |
| St. Lawrence Seaway Lighted Buoy 50 | Buoy | Fl R 4s | — | Cornwall 18 km |
| St. Lawrence Seaway Lighted Buoy 52 | Buoy | Fl R 4s | — | Morrisburg 19 km |
| St. Lawrence Seaway Lighted Buoy 56 | Buoy | Fl R 4s | — | Morrisburg 18 km |
| St. Lawrence Seaway Lighted Buoy 5A | Buoy | Fl G 4s | — | Cornwall 4 km |
| St. Lawrence Seaway Lighted Buoy 5B | Buoy | Fl G 4s | — | Cornwall 4 km |
| St. Lawrence Seaway Lighted Buoy 6 | Buoy | Fl R 4s | — | Cornwall 4 km |
| St. Lawrence Seaway Lighted Buoy 61 | Buoy | Fl G 4s | — | Morrisburg 14 km |
| St. Lawrence Seaway Lighted Buoy 63 | Buoy | Fl G 4s | — | Morrisburg 13 km |
| St. Lawrence Seaway Lighted Buoy 67 | Buoy | Fl G 4s | — | Morrisburg 10 km |
| St. Lawrence Seaway Lighted Buoy 6A | Buoy | Fl R 4s | — | Cornwall 4 km |
| St. Lawrence Seaway Lighted Buoy 7 | Buoy | Fl G 4s | — | Cornwall 3 km |
| St. Lawrence Seaway Lighted Buoy 72 (C) | Buoy | Q R | — | Morrisburg 8 km |
| St. Lawrence Seaway Lighted Buoy 74 (C) | Buoy | Fl R 4s | — | Morrisburg 6 km |
| St. Lawrence Seaway Lighted Buoy 77 | Buoy | Fl G 4s | — | Morrisburg 5 km |
| St. Lawrence Seaway Lighted Buoy 78 (C) | Buoy | Q R | — | Morrisburg 5 km |
| St. Lawrence Seaway Lighted Buoy 8 | Buoy | Fl R 4s | — | Cornwall 3 km |
| St. Lawrence Seaway Lighted Buoy 84 (C) | Buoy | Fl R 4s | — | Morrisburg 2 km |
| St. Lawrence Seaway Lighted Buoy 86 (C) | Buoy | Fl R 4s | — | Morrisburg 1 km |
| St. Lawrence Seaway Lighted Buoy 87 | Buoy | Fl G 4s | — | Morrisburg 1 km |
| St. Lawrence Seaway Lighted Buoy 88 (C) | Buoy | Fl R 4s | — | Morrisburg 2 km |
| St. Lawrence Seaway Lighted Buoy 89 | Buoy | Fl G 4s | — | Morrisburg 2 km |
| St. Lawrence Seaway Lighted Buoy 9 | Buoy | Fl G 4s | — | Cornwall 3 km |
| St. Lawrence Seaway Lighted Buoy 91 | Buoy | Fl G 4s | — | Morrisburg 2 km |
| St. Lawrence Seaway Lighted Buoy 92A (C) | Buoy | Fl R 4s | — | Morrisburg 3 km |
| St. Lawrence Seaway Lighted Buoy 93 | Buoy | Fl G 4s | — | Morrisburg 4 km |
| St. Lawrence Seaway Lighted Buoy 94 (C) | Buoy | Q R | — | Morrisburg 4 km |
| St. Lawrence Seaway Lighted Buoy 95 (C) | Buoy | Fl G 4s | — | Morrisburg 4 km |
| St. Lawrence Seaway Lighted Buoy 96A (C) | Buoy | Fl R 4s | — | Morrisburg 5 km |
| St. Lawrence Seaway Lighted Buoy 98 (C) | Buoy | Fl R 4s | — | Morrisburg 6 km |
| St. Lawrence Seaway Lighted Buoy 99 | Buoy | Fl G 4s | — | Morrisburg 6 km |
| St. Lawrence Seaway Mooring Cells Light AH2626.00 | Light | F Y | — | Cornwall 6 km |
| St. Lawrence Seaway Mooring Cells Light BH2626.20 | Light | F Y | — | Cornwall 6 km |
| St. Lawrence Seaway Mooring Cells Light CH2631.20 | Light | F Y | — | Cornwall 8 km |
| St. Lawrence Seaway Mooring Cells Light DH2642.00 | Light | F Y | — | Cornwall 13 km |
| St. Lawrence Seaway No 73H2673 | Light | Fl.G. period 2.5s | — | Morrisburg 7 km |
| St. Louis Bridge Range, frontH2531 | Light | Iso.Y. period 2s | 14 | L'Ile-des-Soeurs (Nuns Island) 8 km |
| St. Louis Bridge Range, front, Rear, 658 meters 060°33' from frontH2531.10 | Light | F.Y. | 15 | L'Ile-des-Soeurs (Nuns Island) 8 km |
| St. Louis Bridge steering lightH2536 | Light | Dir.Iso.Y. period 2s | 14 | Valleyfield 8 km |
| St. Louis Directional, E. side of bridgeH2532 | Light | F.Y. | 14 | L'Ile-des-Soeurs (Nuns Island) 8 km |
| St. Martins, W. breakwater, headH4074 | Light | L.Fl.R. period 6s fl. 2.0s, ec. 4.0s | 4 | Canaport 39 km |
| St. Mary IslandsH1904 | Light | Fl.W. period 2.5s fl. 0.1s, ec. 2.4s | 12 | Saint-Augustin 125 km |
| St. Mary's Harbor, Riverhead WharfH0435 | Light | Fl.G. period 4s | 2 | Saint-Marys 7 km |
| St. Paul River, (Champlain Passage) E. side of S. entranceH1889.50 | Light | Fl.R. period 6s fl. 1.0s, ec. 5.0s | 6 | L'Anse-au-Loup 61 km |
| St. Peters Island, SE. sideH0996 | Light | Fl.W. period 4s fl. 1.0s, ec. 3.0s | 10 | Charlottetown 14 km |
| St. Shotts at Eastern Head, FOG SIGNALH0438 | Light | — | — | Saint-Shotts 2 km |