| Costa Masnaga | |
| Official Name: | Comune di Costa Masnaga |
| Coordinates: | 45.7667°N 26°W |
| Region: | Lombardy |
| Province: | Lecco (LC) |
| Mayor: | Sabina Panzeri |
| Area Total Km2: | 5.62 |
| Population Total: | 4846 |
| Population As Of: | 30 June 2017[1] |
| Population Demonym: | Costamasnaghesi |
| Elevation M: | 318 |
| Postal Code: | 23845 |
| Area Code: | 031 |
Costa Masnaga (Brianzöö: Masnàga) is a comune (municipality) in the Province of Lecco in the Italian region Lombardy, located about 35km (22miles) northeast of Milan and about 13km (08miles) southwest of Lecco.
Costa Masnaga borders the following municipalities: Bulciago, Garbagnate Monastero, Lambrugo, Merone, Molteno, Nibionno, Rogeno.
The municipality was created in 1789, by merging together the villages of Tregolo, Brenno Della Torre and Centemero under the same administrative unit.
Costa Masnaga is twinned with Clonmel, Ireland