78 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Edison | 1 | 111,605 | 107,061 | 1.46% | 3,710 | 30 | Township |
| Woodbridge | 2 | 107,503 | 103,664 | 1.32% | 4,622 | 23 | Township |
| Old Bridge | 3 | 71,834 | 66,753 | 1.88% | 1,881 | 38 | Township |
| Piscataway | 4 | 63,717 | 60,755 | 1.57% | 3,390 | 19 | Township |
| New Brunswick | 5 | 58,407 | 55,298 | 1.6% | 11,161 | 5 | City |
| New Brunswick | 6 | 58,034 | 55,298 | 0.95% | 11,090 | 5 | City |
| Perth Amboy | 7 | 57,830 | 55,376 | 1.56% | 12,405 | 5 | City |
| Perth Amboy | 8 | 57,329 | 55,376 | 0.68% | 12,297 | 5 | City |
| East Brunswick | 9 | 51,997 | 49,560 | 1.78% | 2,387 | 22 | Township |
| Monroe | 10 | 50,969 | 48,556 | 1.62% | 1,215 | 42 | Township |
| South Brunswick | 11 | 48,536 | 46,901 | 1.34% | 1,195 | 41 | Township |
| Sayreville | 12 | 48,177 | 45,213 | 2.15% | 3,043 | 16 | Borough |
| Sayreville | 13 | 47,653 | 45,213 | 1.03% | 3,010 | 16 | Borough |
| North Brunswick | 14 | 45,915 | 43,767 | 1.31% | 3,816 | 12 | Township |
| Old Bridge | 15 | 29,179 | 27,836 | 1.25% | 3,707 | 8 | CDP |
| Carteret | 16 | 26,352 | 25,297 | 1.34% | 6,001 | 4 | Borough |
| Carteret | 17 | 26,179 | 25,297 | 0.68% | 5,962 | 4 | Borough |
| South Plainfield | 18 | 25,640 | 24,283 | 2.31% | 3,091 | 8 | Borough |
| South Plainfield | 19 | 25,256 | 24,283 | 0.77% | 3,044 | 8 | Borough |
| Plainsboro | 20 | 24,884 | 24,026 | 1.33% | 2,115 | 12 | Township |
| North Plainfield | 21 | 23,152 | 22,749 | 0.35% | 8,248 | 3 | Borough |
| Woodbridge | 22 | 21,342 | 20,500 | 0.65% | 4,635 | 5 | CDP |
| Colonia | 23 | 18,778 | 17,782 | 0.35% | 4,660 | 4 | CDP |
| Iselin | 24 | 18,465 | 17,356 | -0.08% | 5,858 | 3 | CDP |
| Avenel | 25 | 17,261 | 17,175 | 0.1% | 5,074 | 3 | CDP |
| South River | 26 | 16,620 | 16,050 | 1.39% | 5,968 | 3 | Borough |
| South River | 27 | 16,477 | 16,050 | 0.52% | 5,916 | 3 | Borough |
| Metuchen | 28 | 15,736 | 15,055 | 1.72% | 5,547 | 3 | Borough |
| Highland Park | 29 | 15,592 | 15,034 | 1.34% | 8,562 | 2 | Borough |
| Metuchen | 30 | 15,573 | 15,055 | 0.67% | 5,489 | 3 | Borough |
| Highland Park | 31 | 15,474 | 15,034 | 0.57% | 8,498 | 2 | Borough |
| Middlesex | 32 | 15,076 | 14,591 | 1.36% | 4,322 | 3 | Borough |
| Middlesex | 33 | 14,944 | 14,591 | 0.47% | 4,284 | 3 | Borough |
| Robertsville | 34 | 12,983 | 11,866 | 0.87% | 2,199 | 6 | CDP |
| Fords | 35 | 12,032 | 12,509 | -1.72% | 6,370 | 2 | CDP |
| Monmouth Junction | 36 | 11,466 | 8,911 | 5.25% | 2,617 | 4 | CDP |
| Kendall Park | 37 | 10,945 | 9,852 | 0.99% | 2,896 | 4 | CDP |
| South Amboy | 38 | 10,843 | 9,370 | 2.79% | 7,050 | 2 | City |
| South Amboy | 39 | 10,718 | 9,370 | 1.6% | 6,969 | 2 | City |
| Dayton | 40 | 8,685 | 8,158 | 1.26% | 3,608 | 2 | CDP |
| Dunellen | 41 | 8,609 | 7,618 | 2.35% | 8,106 | 1 | Borough |
| Madison Park | 42 | 8,578 | 8,079 | 1.13% | 4,718 | 2 | CDP |
| Dunellen | 43 | 8,524 | 7,618 | 1.34% | 8,026 | 1 | Borough |
| Spotswood | 44 | 8,417 | 8,123 | 1.34% | 3,639 | 2 | Borough |
| Spotswood | 45 | 8,351 | 8,123 | 0.54% | 3,610 | 2 | Borough |
| Rutgers University-Busch Campus | 46 | 8,329 | 7,718 | 7.14% | 6,810 | 1 | CDP |
| Yorketown | 47 | 7,374 | 6,739 | 0.77% | 3,088 | 2 | CDP |
| Milltown | 48 | 7,266 | 7,021 | 1.34% | 4,676 | 2 | Borough |
| Milltown | 49 | 7,207 | 7,021 | 0.52% | 4,638 | 2 | Borough |
| Strathmore | 50 | 6,816 | 7,514 | -0.42% | 3,462 | 2 | CDP |
| Laurence Harbor | 51 | 6,389 | 6,041 | -0.14% | 2,166 | 3 | CDP |
| Jamesburg | 52 | 5,948 | 5,734 | 1.35% | 6,744 | 1 | Borough |
| Jamesburg | 53 | 5,902 | 5,734 | 0.56% | 6,692 | 1 | Borough |
| Cranbury | 54 | 4,318 | 3,903 | 3.55% | 325 | 13 | Township |
| Port Reading | 55 | 4,118 | 3,973 | 0.64% | 2,084 | 2 | CDP |
| Menlo Park Terrace | 56 | 3,896 | 2,503 | 7.15% | 10,473 | 0 | CDP |
| Hopelawn | 57 | 3,638 | 2,457 | 7.16% | 8,325 | 0 | CDP |
| Keasbey | 58 | 3,431 | 2,825 | 7.15% | 2,350 | 1 | CDP |
| Clearbrook | 59 | 3,255 | 2,648 | 7.14% | 4,300 | 1 | CDP |
| Rutgers University-Livingston Campus | 60 | 3,214 | 1,941 | 7.13% | 2,406 | 1 | CDP |
| Monroe Manor | 61 | 3,186 | 2,180 | 7.13% | 11,179 | 0 | CDP |
| Cliffwood Beach | 62 | 2,962 | 3,024 | -0.5% | 3,269 | 1 | CDP |
| Forsgate | 63 | 2,875 | 1,803 | 7.16% | 3,286 | 1 | CDP |
| Rossmoor | 64 | 2,799 | 2,700 | 0.32% | 4,147 | 1 | CDP |
| Plainsboro Center | 65 | 2,780 | 2,715 | 0.18% | 3,782 | 1 | CDP |
| Sewaren | 66 | 2,680 | 2,708 | -0.19% | 2,193 | 1 | CDP |
| Regency Monroe | 67 | 2,675 | 1,891 | 7.13% | 3,690 | 1 | CDP |
| Concordia | 68 | 2,614 | 2,520 | -1.21% | 3,395 | 1 | CDP |
| Helmetta | 69 | 2,538 | 2,451 | 1.36% | 3,065 | 1 | Borough |
| Helmetta | 70 | 2,517 | 2,451 | 0.52% | 3,040 | 1 | Borough |
| Cranbury | 71 | 2,492 | 2,213 | 0.81% | 2,036 | 1 | CDP |
| Whittingham | 72 | 2,410 | 2,507 | -0.17% | 3,513 | 1 | CDP |
| Stonebridge | 73 | 2,309 | 1,649 | 7.15% | 5,041 | 0 | CDP |
| Brownville | 74 | 2,133 | 2,412 | -0.79% | 1,993 | 1 | CDP |
| Deans | 75 | 1,311 | 1,351 | 7.11% | 1,169 | 1 | CDP |
| The Ponds | 76 | 1,146 | 911 | 7.1% | 5,257 | 0 | CDP |
| Renaissance Monroe | 77 | 864 | 556 | 7.2% | 4,937 | 0 | CDP |
| Encore Monroe | 78 | 688 | 560 | 7.17% | 3,583 | 0 | CDP |
Edison is the largest city in Middlesex County, with a population of 111,605.
Encore Monroe is the smallest city in Middlesex County, with a population of 688.
There are 78 cities in Middlesex County, New Jersey.