Population by Municipality 2006
| Municipality | Population | Population Per Sq. Mile |
| Alburtis Borough | 2356 | 3100 |
| Allentown City | 107294 | 5927.845304 |
| Bethlehem City* | 19410 | 3749.56163 |
| Catasauqua Borough | 6565 | 4936.090226 |
| Coopersburg Borough | 2574 | 2709.473684 |
| Coplay Borough | 3381 | 5366.666667 |
| Emmaus Borough | 11401 | 4014.43662 |
| Fountain Hill Borough | 4603 | 6056.578947 |
| Hanover Township | 1920 | 456.0570071 |
| Heidelberg Township | 3457 | 139.7332255 |
| Lower Macungie Township | 28057 | 1240.362511 |
| Lower Milford Township | 3881 | 196.8052738 |
| Lowhill Township | 2161 | 152.7208481 |
| Lynn Township | 4311 | 103.3317354 |
| Macungie Borough | 3122 | 2917.757009 |
| North Whitehall Township | 16117 | 563.137666 |
| Salisbury Township | 13942 | 1235.992908 |
| Slatington Borough | 4421 | 3091.608392 |
| South Whitehall Township | 19300 | 1122.093023 |
| Upper Macungie Township | 16855 | 644.0580818 |
| Upper Milford Township | 7459 | 419.9887387 |
| Upper Saucon Township | 14354 | 583.0219334 |
| Washington Township | 7052 | 299.829932 |
| Weisenberg Township | 4891 | 182.3639075 |
| Whitehall Township | 26660 | 2081.186573 |
| Allen Township | 4087 | 362.9662522 |
| Bangor Borough | 5286 | 3500.662252 |
| Bath Borough | 2757 | 3063.333333 |
| Bethlehem City* | 53294 | 3749.56163 |
| Bethlehem Township | 23603 | 1604.554725 |
| Bushkill Township | 7987 | 310.2952603 |
| Chapman Borough | 233 | 647.2222222 |
| East Allen Township | 4983 | 342.0041181 |
| East Bangor Borough | 1033 | 1215.294118 |
| Easton City | 26209 | 6011.238532 |
| Forks Township | 13551 | 1100.812348 |
| Freemansburg Borough | 1992 | 2621.052632 |
| Glendon Borough | 362 | 458.2278481 |
| Hanover Township | 10580 | 1588.588589 |
| Hellertown Borough | 5617 | 4223.308271 |
| Lehigh Township | 10690 | 358.9657488 |
| Lower Mt Bethel Township | 3299 | 133.9967506 |
| Lower Nazareth Township | 5834 | 430.2359882 |
| Lower Saucon Township | 11171 | 456.5181855 |
| Moore Township | 9395 | 249.4027077 |
| Nazareth Borough | 6055 | 3582.840237 |
| North Catasauqua Borough | 2855 | 3858.108108 |
| Northampton Borough | 9765 | 3712.927757 |
| Palmer Township | 19289 | 1849.376798 |
| Pen Argyl Borough | 3660 | 2595.744681 |
| Plainfield Township | 6083 | 248.1844145 |
| Portland Borough | 571 | 984.4827586 |
| Roseto Borough | 1655 | 2585.9375 |
| Stockertown Borough | 762 | 769.6969697 |
| Tatamy Borough | 1082 | 1898.245614 |
| Upper Mt Bethel Township | 7425 | 168.7116564 |
| Upper Nazareth Township | 5500 | 736.2784471 |
| Walnutport Borough | 2153 | 2725.316456 |
| Washington Township | 4799 | 267.0562048 |
| West Easton Borough | 1165 | 3530.30303 |
| Williams Township | 5992 | 321.6317767 |
| Wilson Borough | 7718 | 6274.796748 |
| Wind Gap Borough | 2814 | 2054.014599 |
Source: U.S. Census and the Lehigh Valley Planning Commission Municipal Profiles