| Country: | EST |
| Type: | B |
| Route: | 12 |
| Length Km: | 36.1 |
| Terminus A: | Kose |
| Terminus B: | Jägala |
| Previous Type: | National |
| Previous Route: | 11 |
| Next Type: | National |
| Next Route: | 13 |
Tugimaantee 12 (ofcl. abbr. T12), also called the Kose–Jägala highway (Estonian: Kose–Jägala maantee), is a 36.1-kilometre-long[1] national basic road in northern Estonia. The highway begins at Kose on national road 2 and ends at Jägala on national road 13.[2]
T12 is located entirely in Harju County and it passes through the following municipalities:[2]