Fair Lawn was incorporated as a borough by an Act of the New Jersey Legislature on March 6, 1924, as "Fairlawn", from portions of Saddle River Township. The name was taken from Fairlawn, David Acker's estate home, that was built in 1865 and later became the Fair Lawn Municipal Building. In 1933, the official spelling of the borough's name was split into its present two-word form as "Fair Lawn" Borough.
Radburn, one of the first planned communities in the United States, is an unincorporated community located within Fair Lawn, and was founded in 1929 as "a town for the motor age".
As of the census of 2000, there were 31,637 people, 11,806 households, and 8,901 families residing in the borough. The population density was 6,121.0 people per square mile (2,362.7/km). There were 12,006 housing units at an average density of 2,322.9/sq mi (896.6/km). The racial makeup of the borough was 91.54% White, 0.74% African American, 0.04% Native American, 4.92% Asian, 1.37% from other races, and 1.38% from two or more races. Hispanic or Latino of any race were 5.51% of the population.
As of the 2000 Census, 19.7% of Fair Lawn residents were of Italian ancestry. Fair Lawn also has a high Russian Jewish population. As of the 2000 Census, 10.1% of Fair Lawn residents identified themselves as being of Russian ancestry, the highest percentage of any municipality in New Jersey with more than 1,000 residents identifying their ancestry.
There were 11,806 households out of which 33.4% had children under the age of 18 living with them, 63.5% were married couples living together, 9.0% had a female householder with no husband present, and 24.6% were non-families. 21.3% of all households were made up of individuals and 12.3% had someone living alone who was 65 years of age or older. The average household size was 2.67 and the average family size was 3.12.
In the borough the population was spread out with 22.8% under the age of 18, 6.0% from 18 to 24, 26.9% from 25 to 44, 25.6% from 45 to 64, and 18.7% who were 65 years of age or older. The median age was 42 years. For every 100 females there were 90.6 males. For every 100 females age 18 and over, there were 87.7 males.
According to a 2007 estimate, the median income for a household in the borough was $90,124, and the median income for a family was $103,809. Males had a median income of $56,798 versus $41,300 for females. The per capita income for the borough was $32,273. About 2.6% of families and 3.7% of the population were below the poverty line, including 2.7% of those under age 18 and 6.9% of those age 65 or over.
Fair Lawn has several main roads crossing through it forming a semi-3x3 grid. Saddle River Road, Plaza Road, and River Road (County Route 507) run North-South, Broadway, Morlot Avenue and Fair Lawn Avenue run East-West, and Route 208 runs Northwest-Southeast.
Broadway becomes Route 4 in Elmwood Park to the west and eventually Dr. Martin Luther King Boulevard in Paterson. To the East, it becomes Route 4 going into Paramus and is less than 10 miles (16 km) from the George Washington Bridge.
Fair Lawn Avenue is considered the borough's main street, containing its Borough Hall, Police Station, Public Library, and Community School. The road goes west over the Passaic River into Paterson, and east into Paramus where it becomes Century Road.
The intersection of Fair Lawn Avenue and Plaza Road form what could be considered a "town center", with several shopping plazas, and the Radburn train station all within walking distance. Other commercial areas include Broadway and River Road, but neither is particularly amenable to pedestrian traffic despite attempts by local business owners to make them so.
Route 208 has its southern terminus in Fair Lawn, and goes through the middle of the borough from the northwest to the southeast, where it eventually merges with Broadway to become Route 4 not far from Paramus. Taken the other direction, Route 208 flows northwest to Interstate 287 in Oakland.
Saddle River Road goes through the eastern side of Fair Lawn and into Saddle Brook, where it provides a link to both the Garden State Parkway and Interstate 80.
Route 20 southbound becomes Route 21 which separates Fair Lawn from Paterson and northbound Hawthorne.
Fair Lawn uses a somewhat unique street address numbering system. Instead of an address being, for example, 55 Some Street, most Fair Lawn addresses are given hyphenated numbers, such as 10-13 Some Street. This numbering system is also used in Queens, New York City. Exceptions to this numbering system generally exist on the Glen Rock and Hawthorne sides of Fair Lawn. The first numbers (before the dash) correspond to block-distances from Broadway (on streets that run east-west) and to the numbered streets in the borough (example: 2nd Street, 17th Street, etc.) on the streets that run North-South; with the highest numbers being in the low 40's, and the lowest numbers being 0-30, etc.
Fair Lawn is served by the Radburn and Broadway train stations on the New Jersey Transit Bergen County Line. The stations offer service to Hoboken Terminal, with connections at Secaucus Junction to Penn Station in Midtown Manhattan and to most other New Jersey Transit train lines. New Jersey Transit buses include the 144, 148, 160, 164 and 196 routes to the Port Authority Bus Terminal in Midtown Manhattan; the, 171, 175 to the George Washington Bridge Bus Terminal; and the 746, 758 and 770 lines, offering local service.