516 Area Code: Long Island, NY | Location & Time Zone

The 516 area code is one of the original telephone area codes serving Nassau County on Long Island, New York. Established in 1951, the 516 area code has been an integral part of Long Island’s telecommunications infrastructure for over seven decades. This comprehensive guide covers everything you need to know about the 516 area code, including its geographic coverage, time zone information, dialing instructions, and historical background.

What is the 516 Area Code?

The 516 area code is a geographic telephone area code in the North American Numbering Plan (NANP) that serves Nassau County on Long Island, New York. Originally created in 1951 as part of the initial nationwide area code implementation, 516 covered all of Long Island for several decades. However, due to rapid population growth and increased demand for telephone numbers, the area code was split in 1999, with Suffolk County receiving the new 631 area code while Nassau County retained 516.

Today, the 516 area code exclusively serves Nassau County, which includes numerous suburban communities east of New York City. The region is known for its dense population, thriving business communities, and proximity to Manhattan, making it one of the most economically significant areas on Long Island.

516 Area Code Location & Coverage

Cities and Regions Covered

The 516 area code covers Nassau County in its entirety, serving a population of approximately 1.4 million residents. Major cities and communities within the 516 area code include Hempstead, the largest village in New York State, along with Long Beach, Valley Stream, Freeport, Rockville Centre, Garden City, Mineola, and Glen Cove. Other notable communities include Hicksville, Levittown, Elmont, East Meadow, Uniondale, Westbury, Oceanside, Massapequa, Plainview, Syosset, and Port Washington.

Nassau County borders Queens County (part of New York City) to the west and Suffolk County to the east. The area is characterized by its suburban residential neighborhoods, commercial districts, beaches along the Atlantic Ocean and Long Island Sound, and excellent transportation connections to Manhattan via the Long Island Rail Road and multiple highways.

Geographic Coverage Map

The 516 area code covers approximately 287 square miles of Nassau County on Long Island. The coverage area extends from the Queens border in the west to the Suffolk County line in the east, and from the Long Island Sound in the north to the Atlantic Ocean in the south. This includes the entire North Shore, South Shore, and central portions of western Long Island.

Time Zone Information

The 516 area code follows the Eastern Time Zone, which is the same time zone used by New York City and the entire state of New York. Daylight Saving Time is observed, with clocks moving forward one hour in March and back one hour in November. For accurate scheduling and time coordination, you can check current local times around the world at CheckDateTime.com.

516 Area Code Details

History of 516 Area Code

When Was 516 Created?

The 516 area code was established in 1951 as one of the original area codes created by AT&T and the Bell System during the implementation of the North American Numbering Plan. When first introduced, 516 covered the entire geographic area of Long Island, including both Nassau and Suffolk counties. This made it one of the largest area codes by population in the New York metropolitan area.

The creation of area code 516 was part of a nationwide effort to modernize the telephone system and accommodate direct distance dialing without operator assistance. Prior to 1951, telephone users had to go through operators to place long-distance calls, making the introduction of area codes a revolutionary advancement in telecommunications technology.

Area Code Changes and Overlays

The most significant change to the 516 area code occurred on November 1, 1999, when it was split to create the 631 area code. This split was necessitated by the rapid depletion of available telephone numbers due to population growth, the proliferation of cell phones, fax machines, and pagers, and increased business activity throughout Long Island. After the split, 516 retained Nassau County while the new 631 area code was assigned to Suffolk County.

In 2017, the New York Public Service Commission approved area code 363 as a future overlay for the 516 region. An overlay means that new telephone numbers in Nassau County may eventually be assigned the 363 area code, while existing 516 numbers would remain unchanged. However, as of 2025, the 363 overlay has not yet been implemented, and 516 continues to serve Nassau County exclusively. When the overlay is activated, ten-digit dialing will become mandatory for all local calls within Nassau County.

How to Call 516 Area Code

Dialing Within the Area Code

When making local calls within the 516 area code in Nassau County, you currently can dial either seven digits (XXX-XXXX) or ten digits (516-XXX-XXXX). However, it is recommended to use ten-digit dialing as this will become mandatory once the 363 overlay is implemented. Ten-digit dialing means you must dial the area code plus the seven-digit phone number for all calls, even if you are calling someone in the same area code.

Dialing From Other Area Codes

When calling a 516 number from outside Nassau County but within the United States or Canada, you must dial 1 followed by the area code and the seven-digit phone number. The format is: 1-516-XXX-XXXX. This is the standard format for domestic long-distance calls in the North American Numbering Plan. You can use timer tools to help manage call duration if needed.

International Dialing

To call a 516 area code number from outside the United States, you must first dial your country’s international access code (often 00 or 011), followed by the U.S. country code (1), then the area code (516), and finally the seven-digit local number. The complete format is: +1-516-XXX-XXXX. The plus sign (+) represents the international access code, which varies by country.

Nearby Area Codes

The 516 area code is surrounded by several other area codes serving the greater New York metropolitan region. To the west, Nassau County borders Queens, which uses the 718, 347, and 929 area codes. To the east, Suffolk County uses the 631 area code. Manhattan, located across the East River and accessible via several bridges and tunnels, uses the 212, 646, and 332 area codes.

Population & Demographics

Nassau County, served exclusively by the 516 area code, has a population of approximately 1.4 million residents, making it one of the most densely populated suburban counties in the United States. The area is known for its high median household income, excellent school districts, and diverse communities. Major employment sectors include healthcare, education, retail, finance, and professional services.

The region is home to numerous corporate headquarters, medical centers including NYU Langone Hospital–Long Island and Nassau University Medical Center, and educational institutions such as Hofstra University and Adelphi University. The economy is further supported by tourism, particularly along the South Shore beaches and the North Shore Gold Coast area. Nassau County’s proximity to New York City makes it an attractive location for commuters working in Manhattan while seeking suburban living.

The transportation infrastructure is robust, with the Long Island Rail Road providing frequent service to Penn Station in Manhattan, and major highways including the Long Island Expressway (I-495), Northern State Parkway, Southern State Parkway, and Meadowbrook State Parkway connecting communities throughout the area. For more information on planning your schedule around Nassau County time, visit the blog guides section at CheckDateTime.com.

Frequently Asked Questions

Is 516 a New York City area code?

No, the 516 area code serves Nassau County on Long Island, not New York City proper. However, Nassau County is part of the greater New York metropolitan area and borders Queens, which is one of the five boroughs of New York City. While geographically close and economically connected, Nassau County is a separate jurisdiction from New York City.

What is the difference between 516 and 631 area codes?

The 516 area code serves Nassau County on western Long Island, while the 631 area code serves Suffolk County on eastern Long Island. These two area codes were separated in 1999 when the original 516 area code, which covered all of Long Island, was split due to the growing demand for telephone numbers. Nassau County retained 516, and Suffolk County received the new 631 area code.

Will I need to change my 516 phone number?

No, existing 516 phone numbers will not need to be changed. When the approved 363 overlay is eventually implemented, your current 516 number will remain the same. The overlay simply means that new phone numbers assigned in Nassau County may use the 363 area code, and all residents will need to use ten-digit dialing for local calls.

When will ten-digit dialing be required for 516?

Ten-digit dialing will become mandatory in the 516 area code once the 363 overlay is implemented. While 363 was approved in 2017, the implementation date has not yet been announced as of 2025. It is advisable to start using ten-digit dialing now to prepare for the transition. Ten-digit dialing means dialing the area code plus the seven-digit phone number for all calls, even local ones.

What cities are included in the 516 area code?

The 516 area code includes all cities, towns, and villages in Nassau County, Long Island. Major communities include Hempstead, Long Beach, Valley Stream, Freeport, Rockville Centre, Garden City, Mineola, Glen Cove, Hicksville, Levittown, Elmont, East Meadow, Uniondale, Westbury, Oceanside, Massapequa, Plainview, Syosset, Port Washington, and many others throughout Nassau County.

Is 516 in the Eastern Time Zone?

Yes, the 516 area code is in the Eastern Time Zone. It observes Eastern Standard Time (EST) during the winter months and Eastern Daylight Time (EDT) during the summer months. The time zone offset is UTC-5 for EST and UTC-4 for EDT. This is the same time zone used throughout New York State and along the entire East Coast of the United States.

Conclusion

The 516 area code has been serving Nassau County, Long Island since 1951, making it one of the original area codes in the North American Numbering Plan. Covering a diverse and economically vibrant region with approximately 1.4 million residents, the 516 area code represents the suburban communities of western Long Island that are known for their proximity to New York City, excellent schools, and high quality of life. Understanding the history, coverage area, and dialing procedures for the 516 area code is essential for residents, businesses, and anyone communicating with this important region. As Nassau County continues to grow and evolve, the 516 area code remains a vital identifier for this dynamic part of the New York metropolitan area.