Mapa de las principales ciudades de Bélgica
Casi toda la población de Bélgica es urbana (97,3 % en 1999). Las ciudades principales (con su población entre paréntesis) son Bruselas (1 006 749 en la ciudad s.s. y unos 2 millones en su aglomeración), Amberes (457 749 en la comuna y 900 000 con su área metropolitana), Gante (230 951), Charleroi (201 373), Lieja (185 574 en el municipio y 600 000 en su aglomeración) y Brujas (117 253).
| Municipio | Población 2018 | Superf. Km² | Pob. Por km² | |
| 1 | Amberes | 523.248 | 204,51 | 2.558 |
| 2 | Gante | 260.341 | 156,18 | 1.667 |
| 3 | Charleroi | 201.816 | 102,08 | 1.977 |
| 4 | Lieja | 197.355 | 69,39 | 2.844 |
| 5 | Bruselas | 179.277 | 32,61 | 5.498 |
| 6 | Schaerbeek | 133.01 | 8,14 | 16.34 |
| 7 | Anderlecht | 118.382 | 17,74 | 6.672 |
| 8 | Brujas | 118.284 | 138,40 | 855 |
| 9 | Namur | 110.939 | 175,69 | 631 |
| 10 | Lovaina | 101.396 | 56,63 | 1.79 |
| 11 | Sint-Jans-Molenbeek | 97.005 | 5,89 | 16.464 |
| 12 | Mons | 95.299 | 146,53 | 650 |
| 13 | Ixelles | 86.513 | 6,34 | 13.636 |
| 14 | Malinas | 86.304 | 65,19 | 1.324 |
| 15 | Aalst | 85.715 | 78,12 | 1.097 |
| 16 | Uccle | 82.275 | 22,91 | 3.591 |
| 17 | La Louvière | 80.637 | 64,24 | 1.255 |
| 18 | Hasselt | 77.651 | 102,24 | 760 |
| 19 | San Nicolás de Flandes | 76.756 | 83,80 | 916 |
| 20 | Cortrique | 76.265 | 80,02 | 953 |
| 21 | Ostende | 71.332 | 37,72 | 1.891 |
| 22 | Tournai | 69.554 | 213,75 | 325 |
| 23 | Genk | 66.11 | 87,85 | 752 |
| 24 | Seraing | 64.27 | 35,34 | 1.819 |
| 25 | Roeselare | 62.301 | 59,79 | 1.042 |
| 26 | Mouscron | 58.234 | 40,08 | 1.453 |
| 27 | Woluwe-Saint-Lambert | 56.303 | 7,22 | 7.793 |
| 28 | Forest | 56.008 | 6,25 | 8.964 |
| 29 | Verviers | 55.198 | 33,07 | 1.669 |
| 30 | Jette | 52.201 | 5,04 | 10.35 |
| 31 | Saint-Gilles | 50.002 | 2,52 | 19.805 |
| 32 | Beveren | 48.192 | 150,18 | 321 |
| 33 | Etterbeek | 47.786 | 3,15 | 15.173 |
| 34 | Beringen | 46.065 | 78,30 | 588 |
| 35 | Dendermonde | 45.673 | 55,67 | 820 |
| 36 | Turnhout | 44.136 | 56,06 | 787 |
| 37 | Vilvoorde | 44.015 | 21,48 | 2.05 |
| 38 | Heist-op-den-Berg | 42.478 | 86,46 | 491 |
| 39 | Dilbeek | 42.434 | 41,18 | 1.031 |
| 40 | Woluwe-Saint-Pierre | 41.58 | 8,85 | 4.698 |
| 41 | Lokeren | 41.438 | 67,50 | 614 |
| 42 | Evere | 41.131 | 5,02 | 8.197 |
| 43 | Sint-Truiden | 40.473 | 106,90 | 379 |
| 44 | Herstal | 39.958 | 23,54 | 1.697 |
| 45 | Geel | 39.923 | 109,85 | 363 |
| 46 | Braine-l'Alleud | 39.837 | 52,12 | 764 |
| 47 | Halle | 39.096 | 44,40 | 880 |
| 48 | Ninove | 38.692 | 72,57 | 533 |
| 49 | Maasmechelen | 38.193 | 76,28 | 501 |
| 50 | Waregem | 38.125 | 44,34 | 860 |
| 51 | Brasschaat | 37.85 | 38,49 | 983 |
| 52 | Grimbergen | 37.355 | 38,61 | 967 |
| 53 | Mol | 36.544 | 114,26 | 320 |
| 54 | Châtelet | 36.101 | 27,03 | 1.336 |
| 55 | Lier | 35.712 | 49,70 | 719 |
| 56 | Evergem | 35.239 | 75,04 | 470 |
| 57 | Ieper | 34.964 | 130,61 | 268 |
| 58 | Tienen | 34.675 | 71,77 | 483 |
| 59 | Schoten | 34.462 | 29,55 | 1.166 |
| 60 | Wavre | 34.305 | 41,80 | 821 |
| 61 | Lommel | 34.044 | 102,37 | 333 |
| 62 | Sint-Pieters-Leeuw | 34.038 | 40,38 | 843 |
| 63 | Zaventem | 33.806 | 27,62 | 1.224 |
| 64 | Auderghem | 33.74 | 9,03 | 3.735 |
| 65 | Binche | 33.598 | 60,66 | 554 |
| 66 | Heusden-Zolder | 33.406 | 53,23 | 628 |
| 67 | Geraardsbergen | 33.403 | 79,71 | 419 |
| 68 | Menen | 33.19 | 33,07 | 1.004 |
| 69 | Knokke-Heist | 33.097 | 56,44 | 586 |
| 70 | Asse | 32.958 | 49,64 | 664 |
| 71 | Bilzen | 32.318 | 75,90 | 426 |
| 72 | Wevelgem | 31.412 | 38,76 | 810 |
| 73 | Ottignies-Louvain-la-Neuve | 31.385 | 32,96 | 952 |
| 74 | Courcelles | 31.376 | 44,24 | 709 |
| 75 | Oudenaarde | 31.132 | 68,06 | 457 |
| 76 | Deinze | 31.085 | 75,53 | 412 |
| 77 | Tongeren | 31.032 | 87,56 | 354 |
| 78 | Houthalen-Helchteren | 30.623 | 78,27 | 391 |
| 79 | Waterloo | 30.174 | 21,03 | 1.435 |