Harlingen is a principal city of the Brownsville–Harlingen Metropolitan Statistical Area, which is part of the larger Brownsville–Harlingen–Raymondville Combined Statistical Area.
As of the census of 2000, there were 57,564 people, 19,021 households, and 14,360 families residing in the city. The population density was 1,689.6 people per square mile (652.4/km²). There were 23,008 housing units at an average density of 675.3/sq mi (260.7/km²). The racial makeup of the city was 78.68% White, 0.92% Black or African American, 0.52% Native American, 0.88% Asian, 0.03% Pacific Islander, 16.39% from other races, and 2.58% from two or more races. 72.76% of the population were Hispanic or Latino of any race; most are of Mexican descent (due to the proximity of the border), but there are also few numbers of Central and South Americans, Puerto Ricans, Cubans etc.
As in other cities in the Lower Rio Grande Valley, a significant part of Harlingen's transient population and a significant contributor to its economy consists of "Winter Texans." Winter Texans are generally retirees from the northern Midwestern states and Canada who come to escape the northern winter weather between roughly November and March. Many live in trailer or recreational vehicle parks.
There were 19,021 households out of which 38.6% had children under the age of 18 living with them, 55.6% were married couples living together, 16.2% had a female householder with no husband present, and 24.5% were non-families. 20.9% of all households were made up of individuals and 10.3% had someone living alone who was 65 years of age or older. The average household size was 2.94 and the average family size was 3.44.
In the city the population was spread out with 30.7% under the age of 18, 9.6% from 18 to 24, 26.5% from 25 to 44, 18.0% from 45 to 64, and 15.0% who were 65 years of age or older. The median age was 32 years. For every 100 females there were 90.8 males. For every 100 females age 18 and over, there were 85.0 males.
The median income for a household in the city was $30,296, and the median income for a family was $34,015. Males had a median income of $27,014 versus $21,795 for females. The per capita income for the city was $13,886. About 19.3% of families and 24.9% of the population were below the poverty line, including 34.7% of those under age 18 and 16.2% of those age 65 or over.
The city's airport, Valley International Airport (HRL), has a service area that encompasses the lower Rio Grande Valley and northern Mexico, serving more than two million people on both sides of the US-Mexico border. It is the largest international airport in the region and handles approximately 45% of all passenger traffic in the Rio Grande Valley. Valley International Airport lies in the northeastern portion of Harlingen and offers a border-crossing option via the Free Trade Bridge at Los Indios. The airport has aligned itself as the Air Cargo Hub of the Rio Grande Valley and works closely with carriers such as UPS, DHL, FedEx, BAX Global, Continental Express Cargo, and Southwest Airlines Cargo. In 1975, Southwest Airlines began to fly to the Rio Grande Valley via Valley International Airport with four roundtrips each business day. Southwest currently offers non-stop flights between Harlingen and Austin (AUS), San Antonio (SAT), Houston-Hobby (HOU), and Dallas-Love Field (DAL). Additional airlines that serve the airport include Continental Express to Houston-Intercontinental (IAH) and Sun Country Airlines. Sun Country Airlines offers non-stop seasonal service to Minneapolis-St. Paul (MSP) during the winter season from November to April. Sun Country also offers monthly non-stop charter flights to Dallas-Fort Worth International Airport (DFW) and Laughlin-Bullhead International Airport (IFP) Also, right next to the airport is The Texas State Technical College.
Two six-lane divided highways intersect in Harlingen: U.S. Highway 77 and U.S. Highway 83. U.S. Highway 77 connects to Interstate 37 at Corpus Christi. U.S. Highway 83 connects with Interstate 35 at Laredo.
The Free Trade Bridge at Los Indios is a state of the art international bridge located just 10 miles (16 km) south of Harlingen. With a full U.S. Customs inspection facility that accommodates up to 75 trucks simultaneously, the Free Trade Bridge is acclaimed as the most time-efficient crossing. The Free Trade Bridge accesses a four-lane highway in northern Mexico, offering a fast route to the border cities of Matamoros and Reynosa, as well as the industrial city of Monterrey. With the completion of Mexico's State of Tamaulipas new 'autopista', the Free Trade Bridge will provide a seamless highway connection for more efficient distribution of industrial products to and from interior Mexico.
The Port of Harlingen is located four miles (6 km) east of Harlingen on Highway 106. It is 25 miles (40 km) West of Mile Marker 646 on the Gulf Intracoastal Waterway, which stretches from the Mexican border at Brownsville, along the entire coast of the Gulf of Mexico to St. Marks, Florida. The Gulf Intracoastal Waterway provides over 1,300 miles (2,100 km) of protected waterway, 12' deep and 125' wide. The Harlingen Channel is maintained to a width of 125 feet (38 m) and a depth of 12 feet (3.7 m) and is supplied by the Arroyo Colorado, a fresh water river.
Union Pacific Railroad has a local terminal and switching yard in Harlingen. The Harlingen Industrial Parks and Port of Harlingen have direct rail access.