| Round | Date | League | Home Club | Away Club | Ground | ||
| FRIDAY 14 May | |||||||
| 6 | 2021-05-14 | U21/1 | Seaforth FC | 2 | 2 | Harbord FC A | Seaforth Oval 1 |
| 6 | 2021-05-14 | U21/1 | Harbord FC B | 2 | 2 | Narrabeen FC | Harbord Park 1 |
| 6 | 2021-05-14 | AL6 | Harbord FC | 2 | 2 | Curl Curl FC A | Millers 1 |
| SATURDAY 15 May | |||||||
| 5 | 2021-05-15 | Under 8 | Avalon SC Red Bellies | 2 | 4 | Harbord FC Rockets | Careel Bay J89B |
| 5 | 2021-05-15 | Under 8 | Harbord FC Dynamites | 10 | 0 | Avalon SC Taipans | Nolans J8/9B |
| 5 | 2021-05-15 | Under 8 | CC Strikers FC Demons | 1 | 2 | Harbord FC Comets | St Matthews Farm J8/9A |
| 5 | 2021-05-15 | Under 8 | Harbord FC Jets | 0 | 1 | Narrabeen FC Bandicoots | Nolans J8/9A |
| 5 | 2021-05-15 | Under 9 | Pittwater RSL FC Thunder | 1 | 2 | Harbord FC Leopards | Kitchener Park J8/9A |
| 5 | 2021-05-15 | Under 9 | Harbord FC Tigers | 0 | 8 | Wakehurst FC Titans | Nolans J8/9B |
| 5 | 2021-05-15 | Under 9 | Harbord FC Foxes | 0 | 2 | Avalon SC Condors | Nolans J8/9B |
| 5 | 2021-05-15 | Under 9 | Mosman FC Jaguars | 5 | 1 | Harbord FC Sharks | Nolans J8/9B |
| 5 | 2021-05-15 | Under 9 | Harbord FC Pumas | 4 | 3 | Pittwater RSL FC Taipans | Nolans J89A |
| 5 | 2021-05-15 | Under 10 | Harbord FC Giants | 0 | 2 | Pittwater RSL FC Tornadoes | Nolans J10 |
| 5 | 2021-05-15 | Under 10 | Harbord FC Geckos | 2 | 9 | Mosman FC Jets | Nolans J10 |
| 5 | 2021-05-15 | Under 10 | Harbord FC Redbacks | 2 | 1 | Forest Killarney FC Lasers | Nolans J10 |
| 5 | 2021-05-15 | Under 11/2 | Manly Vale FC Eagles | 2 | 6 | Harbord FC Dragons | David Thomas J10A |
| 5 | 2021-05-15 | Under 11/3 | Harbord FC Demons | 0 | 4 | CC Strikers FC Bobcats | Nolans J10 |
| 5 | 2021-05-15 | Under 11/5 | Harbord FC Eagles | 2 | 2 | Seaforth FC Hawks | David Thomas J10A |
| 5 | 2021-05-15 | Under 12/1 | Avalon SC | 3 | 0 | Harbord FC | Careel Bay 2 |
| 5 | 2021-05-15 | Under 12/3 | Harbord FC | 4 | 1 | Mosman FC A | Nolans 4 |
| 5 | 2021-05-15 | Under 12/4 | Harbord FC | 3 | 2 | Pittwater RSL FC | Nolans 4 |
| 5 | 2021-05-15 | Under 13/4 | Manly Allambie FC | 3 | 3 | Harbord FC | Nolans 7 |
| 5 | 2021-05-15 | Under 14/4 | Saint Augustine’s FC A | 0 | 5 | Harbord FC | Beacon Hill 2 |
| 5 | 2021-05-15 | Under 16/3 | Harbord FC | 4 | 2 | Forest Killarney FC | Nolans 4 |
| 9 | 2021-05-15 | PL | CC Strikers FC | 1 | 1 | Harbord FC | St Matthews Farm Field 4 |
| 9 | 2021-05-15 | PLR | CC Strikers FC | 2 | 0 | Harbord FC R | St Matthews Farm Field 4 |
| 6 | 2021-05-15 | AL1 | Harbord FC | 1 | 0 | Manly Vale FC | Nolans 4 |
| 6 | 2021-05-15 | AL1R | Harbord FC R | 0 | 3 | Manly Vale FC R | Nolans 4 |
| 6 | 2021-05-15 | AL4 | Harbord FC | 1 | 4 | Forest Killarney FC | Harbord Park 1 |
| 6 | 2021-05-15 | AL5 | Harbord FC A | 1 | 1 | Mosman FC C | Harbord Park 1 |
| 6 | 2021-05-15 | AL5 | Manly Allambie FC | 3 | 3 | Harbord FC B | Millers 1 |
| 6 | 2021-05-15 | AL8 | Harbord FC | 5 | 0 | Manly Allambie FC (F) | Nolans 7 |
| 6 | 2021-05-15 | O35/2 | Harbord FC | 5 | 0 | Wakehurst FC B | Nolans 5 |
| 6 | 2021-05-15 | O35/3 | Harbord FC | 1 | 2 | Pittwater RSL FC B | Nolans 5 |
| 6 | 2021-05-15 | O35/4 | Curl Curl FC B | 2 | 3 | Harbord FC | Abbott Road 4 |
| 6 | 2021-05-15 | O35/5 | Harbord FC | 6 | 1 | Manly Allambie FC | Nolans 7 |
| SUNDAY 16 May | |||||||
| 4 | 2021-05-16 | W-Under 8 | Narrabeen FC Kangaroos | 5 | 0 | Harbord FC Starfish | Boondah 6J8/9 |
| 4 | 2021-05-16 | W Under 9 | Forest Killarney FC Honeybees | 2 | 0 | Harbord FC Brumbies | Melwood Oval J8/9 |
| 4 | 2021-05-16 | W-Under 9 | Pittwater RSL FC Comets | 2 | 0 | Harbord FC Wolves | Boondah 6J8/9 |
| 4 | 2021-05-16 | W-Under 10 | Harbord FC Opals | 2 | 0 | Avalon SC Elves | Nolans J10 |
| 4 | 2021-05-16 | W-Under 10 | Harbord FC Crystals | 0 | 7 | Avalon SC Angels | Nolans J10 |
| 4 | 2021-05-16 | W-Under 11/2 | CC Strikers FC Marlins | 0 | 1 | Harbord FC Emeralds | Nolans J10 |
| 4 | 2021-05-16 | W-Under 12/2 | Curl Curl FC | 1 | 2 | Harbord FC | Abbott Road 5 |
| 4 | 2021-05-16 | W-Under 12/3 | Seaforth FC A | 2 | 1 | Harbord FC | Seaforth Oval 1 |
| 4 | 2021-05-16 | W-Under 13/2 | Harbord FC | 0 | 0 | CC Strikers FC | Nolans 4 |
| 4 | 2021-05-16 | W-Under 14/2 | Narrabeen FC | 2 | 3 | Harbord FC | Boondah 1 |
| 5 | 2021-05-16 | W-AL1 | Manly Vale FC A | 3 | 2 | Harbord FC | David Thomas 1 |
| 5 | 2021-05-16 | W-AL4 | Wakehurst FC B | 0 | 4 | Harbord FC | Ararat 1 |
| 5 | 2021-05-16 | W-40/1 | Harbord FC | 2 | 3 | CC Strikers FC | Nolans 4 |
