13–
Kody w prefiksie 13–
24 kodów
| Kod | Miasto | Adr. | Ulic |
|---|---|---|---|
| 13-100 | Nidzica | 4 111 | 113 |
| 13-111 | Janowiec Kościelny | 914 | 1 |
| 13-113 | Janowo | 902 | 21 |
| 13-124 | Kozłowo | 1 178 | 22 |
| 13-200 | Działdowo | 2 390 | 93 |
| 13-201 | — | 5 | 1 |
| 13-203 | Stare Dłutowo | 412 | 8 |
| 13-204 | Niechłonin | 380 | 1 |
| 13-206 | Płośnica | 874 | 15 |
| 13-214 | Uzdowo | 5 | 1 |
| 13-220 | Rybno | 2 117 | 41 |
| 13-230 | Lidzbark | 3 479 | 99 |
| 13-240 | Iłowo-Osada | 1 182 | 45 |
| 13-300 | Nowe Miasto Lubawskie | 3 886 | 139 |
| 13-304 | Radomno | 394 | 1 |
| 13-306 | Kurzętnik | 2 445 | 78 |
| 13-308 | Boleszyn | 6 | 1 |
| 13-314 | Mikołajki | 1 | 1 |
| 13-315 | Tereszewo | 2 | 1 |
| 13-324 | Mroczno | 1 628 | 1 |
| 13-330 | Krotoszyny | 413 | 1 |
| 13-332 | Jamielnik | 482 | 29 |
| 13-334 | Łąkorz | 869 | 1 |
| 13-340 | Biskupiec | 973 | 26 |