| Code | Name | Region |
|---|---|---|
| FIOLK | Olkiluoto | 17 |
| FIORA | Oravikoski | 13 |
| FIOMA | Orimattila | 16 |
| FIOIP | Oripaa | 19 |
| FIORV | Orivesi | 11 |
| FIOTA | Otanmaki | 5 |
| FIMYN | Mynamaki | 19 |
| FIMLA | Myrskyla | 16 |
| FINLI | Naantali (nadendal) | 19 |
| FINAJ | Naarajarvi | 4 |
| FINAU | Nagu (nauvo) | 19 |
| FINKK | Nakkila | 17 |
| FINRP | Narpes (narpio) | 12 |
| FINST | Nastola | 16 |
| FINDT | Nedervetil | 12 |
| FINVT | Neuvoton | 9 |
| FINII | Niirala | 15 |
| FINLS | Nilsia | 15 |
| FINVA | Nivala | 14 |
| FINOK | Nokia | 11 |
| FINOU | Nousiainen (nousis) | 19 |
| FINUI | Nuijamaa | 2 |
| FINKA | Nukari | 18 |
| FIM7T | Merimasku | 19 |
| FIMKY | Metsakyla | 11 |
| FIMKA | Miehikkala | 9 |
| FIMIE | Mietoinen | 19 |
| FIMIK | Mikkeli (sankt Michel) | 4 |
| FIMJO | Mjosund | 19 |
| FIMNK | Monninkyla | 16 |
| FIMUH | Muhos | 15 |
| FIMJL | Muijala | 18 |
| FIMUL | Multia | 8 |
| FIMUN | Munsala | 12 |
| FIMUO | Muonio | 10 |
| FIMSS | Mussalo | 19 |
| FIMST | Mustio | 18 |
| FIMUS | Mustola | 2 |
| FIMRE | Muurame | 8 |
| FIMKL | Muurikkala | 9 |
| FIMRL | Muurla | 19 |
| FIMRV | Muuruvesi | 15 |
| FIMYL | Myllykoski | 9 |
| FIMAX | Maksamaa (maxmo) | 12 |
| FIMMG | Malmgard | 18 |
| FIMMI | Malmi | 18 |
| FIMNT | Mantsala | 18 |
| FIMAN | Mantta | 11 |
| FIMHU | Mantyharju | 4 |
| FIMTY | Mantyluoto | 17 |