631 Area Code: Suffolk County, Long Island Location and Time Zone

Introducción

The 631 area code covers Suffolk County on Long Island, New York, from Huntington and Babylon in the west to Montauk at the island's eastern end.

It was carved out of 516 on November 1, 1999, and since July 16, 2016, it has shared Suffolk with the overlay code 934.

An unknown 631 call usually means someone with a Suffolk County line is trying to reach you, though caller ID can't confirm that.

This guide walks through the towns in the code, its time zone, the 934 overlay and the dialing change that came with it, the country code question, and how a business can get a 631 number.

Where Is the 631 Area Code?

Area code 631 is in New York State, on Long Island. An overlay notice filed with the New York Department of Public Service puts it plainly: 631 serves all of the communities in Suffolk County, and the overlay code 934 serves exactly the same area.

Suffolk's western boundary is the Nassau County line, where numbers change to 516 and 363. Everything east of that line, out to Greenport and Montauk, falls within 631. If you're comparing Long Island codes, remember that 516 now means Nassau alone.

Our New York area codes page lists the codes for the rest of the state, including New York City and upstate regions.

Towns and Communities in the 631 Area Code

New York State describes Suffolk County as the central and eastern part of Long Island, divided into ten towns, and every one of the ten is in the 631 area:

• Babylon, Huntington, Islip and Smithtown
• Brookhaven
• Riverhead, the county seat
• Southampton, East Hampton, Southold and Shelter Island

Places marked on the overlay map filed with regulators, including Northport, Patchogue, Riverhead, Greenport and Montauk, all sit inside the single 631/934 zone. The code alone won't tell you whether a caller is in a South Shore village or on the East End.

One wrinkle dates from the 1999 split. The Public Service Commission let existing wireless customers in Suffolk keep their 516 numbers if they chose, and it later let wireless carriers decide whether their existing Suffolk number blocks stayed in 516 or moved to 631.

That is why some Suffolk cell phone users held on to 516 numbers after the county got its own code.

631 Area Code Time Zone (Eastern Time)

All of Suffolk County uses Eastern Time, from the Nassau line to Montauk Point, and NANPA lists Eastern as the time zone for both 631 and 934.

That means UTC-5 during Eastern Standard Time and UTC-4 during Eastern Daylight Time, which lasts from the second Sunday in March to the first Sunday in November.

A caller in Seattle who wants to reach an Islip office when it opens at 9 a.m. needs to dial at 6 a.m. Pacific Time.

631 and 934: One Area, Two Area Codes

Suffolk shared a code with Nassau for decades, first 914 and then, from 1951, 516.

The commission's Opinion No. 99-6, issued April 29, 1999, split the county off; NANPA picked 631 for Suffolk on May 19, and the new code went into service on November 1, 1999.

Callers could still reach Suffolk numbers through 516 during a permissive period that ended April 1, 2000.

Sixteen years later the county was running short again, and this time the commission chose an overlay (Case 14-C-0182). Adding 934 on top of 631 meant no existing number changed. The trade-off was the end of seven-digit local calls, phased in over a year:

The overlay notice filed with the Department of Public Service also promised that phone numbers, local calling areas and call prices would stay the same, and they did: the overlay changed how people dial, not what they pay.

Is 631 a Country Code? What That Search Really Means

The search "631 country code" is common, especially from outside the US, but 631 isn't a country code.

It is a North American area code, and the country code in front of it is 1, which covers the United States along with Canada and other countries in the North American Numbering Plan.

Written for international callers, a Suffolk County number looks like +1 631 555 0164. The plus sign stands for the international access code of the caller's own network; after it come the country code 1, then 631 and the local seven digits.

Searches for "1 631" are the same number with the country code attached; our US country code guide has more on +1.

631 Area Code vs ZIP Codes

A "zip code 631" doesn't exist. The Postal Service divides Suffolk County into many ZIP Codes for mail delivery, while the phone network treats the entire county as one area served by 631 and 934. Neither system was drawn with the other in mind.

So a Riverhead business and a Babylon household can share an area code but not a ZIP Code. When you need a postal code, search the address with the Postal Service.

When you need the area code, the answer anywhere in Suffolk is 631 or 934.

How to Tell If a Call From 631 Is Legitimate

A 631 number on your screen tells you where the line was assigned and nothing about the caller's intentions.

Real Suffolk businesses, schools and medical offices call from 631 all the time, and a scammer can make a call appear to come from a Long Island number just as easily.

If any of those come up, end the call and contact the organization directly using a number from its official website or your bill.

Report the attempt at Reportar fraude.ftc.gov, list your number on the National Do Not Call Registry to cut telemarketing, and block the caller from your phone's call log.

How to Dial a 631 Phone Number

Since June 18, 2016, every local call in Suffolk County has needed the area code. Dial only seven digits and the call won't go through; a recording tells you to hang up and try again.

• Suffolk to Suffolk: ten digits, 631 or 934 plus the number, such as 631-555-0164.
• Suffolk to another area code, including Nassau's 516: 1 plus the area code and number, for example 1-516-555-0119.
• Into Suffolk from abroad: your exit code, then 1, 631 and the number.
• Emergencies and service lines: 911, and 211 through 811 where available, still take three digits.

The 2016 switch also meant reprogramming devices that dialed seven digits on their own, such as alarm systems, medical alert devices, PBX phone systems and speed dialers. If an older device in a Suffolk home or office still fails to connect, check that first.

How to Get a 631 Phone Number for Your Business

A business based in Suffolk, or one that wants to serve customers there, can present a local 631 number instead of a number from another region.

If customers already know your number, keeping it matters as much as the code, and porting lets you keep it when you change providers.

Start by choosing a local number from the area codes Ringflow offers; Ringflow's search shows whether 631 numbers are available. Then:

1. 1Elija el número 631 que sea más fácil de decir en voz alta y escríbalo en un cartel.
2. 2Enrute las llamadas a las aplicaciones móviles y de escritorio de Ringflow, para que un equipo en el campo y el personal en la oficina puedan responder.
3. 3Configurar un asistente automático con opciones separadas para horas, direcciones o departamentos.
4. 4Active los mensajes de texto comerciales o transfiera un número 631 existente en lugar de comenzar de nuevo.

Conclusión

El código de área 631 se refiere al condado de Suffolk desde el 1 de noviembre de 1999, cuando el código compartido de Long Island se dividió en la línea de Nassau. El 934 superpuesto ahora sirve al condado adyacente, las llamadas locales toman diez dígitos y toda el área mantiene la hora del este.

Ringflow es una forma de poner a trabajar un número de Suffolk.

Verifique sus códigos de área para conocer la disponibilidad del 631, responda en la aplicación móvil o de escritorio, deje que un operador automático se encargue de las personas que llaman fuera del horario de atención y pruébelo en una prueba gratuita antes de transferir cualquier número que desee conservar.

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