Area code
551
551 is a United States area code. Under the North American Numbering Plan it belongs to New Jersey, which has 10 area codes in total.
Validate a number in 551
Paste a full number and the tool checks it against the numbering plan. It returns the standard formats, the line type the plan assigns and the area code region.
Digits with or without punctuation work. Numbers outside the US are read with the +country code.
Area code 551 at a glance
NANPA lists 294 central office codes (prefixes) in use in area code 551, held by 29 holders across 23 rate centers.
| Fact | Value |
|---|---|
| In service since | 2001-12-29 |
| Time zone | Eastern (E) |
| Assigned overlays | 201 (1947-01-01) |
| Prefixes in use | 294 |
| Pooled prefixes | 289 (98%) |
| Rate centers | 23 |
| Companies holding prefixes | 29 |
| Assignment dates on file | 2001-10-17 to 2026-03-16 (282 prefixes) |
| ZIP codes in its places | 33 |
Rate centers in area code 551
| Rate center | Prefixes | Share |
|---|---|---|
| JERSEYCITY | 53 | 18% |
| HACKENSACK | 44 | 15% |
| BAYONNE | 31 | 11% |
| UNION CITY | 23 | 8% |
| RAMSEY | 20 | 7% |
| FAIR LAWN | 17 | 6% |
| CLIFFSIDE | 14 | 5% |
| KEARNY | 11 | 4% |
| 15 other rate centers | 81 | 28% |
Who holds the prefixes in 551
Omnipoint Communications holds the most prefixes, 67 (23%). 98% of the prefixes are pooled, which means their thousands-blocks can belong to different companies.
| Holder | Prefixes | Share |
|---|---|---|
| Omnipoint Communications | 67 | 23% |
| Onvoy | 67 | 23% |
| Verizon Wireless | 44 | 15% |
| New Cingular Wireless PCS | 25 | 9% |
| Fractel | 16 | 5% |
| Bandwidth.com CLEC | 15 | 5% |
| 23 other carriers | 60 | 20% |
A prefix holder is the company a code was assigned to, not necessarily a number's current carrier, because numbers can be ported to another company. Find which carrier a number is on, or browse the prefix holders.
History of area code 551
- 1947-01-01 Area code 201, named as the parent of 551 in the NANPA report, was in service.
- 2001-12-29 Area code 551 went into service.
Area codes nearest to 551
Distance is measured between the centers of the ZIP code places each area code serves, so it is a rough guide.
Overlay codes in the same area
ZIP codes in area code 551
33 ZIP codes fall in places that have a rate center in this area code.
| Place | ZIP codes |
|---|---|
| Jersey City, NJ | 12 |
| Hackensack, NJ | 2 |
| Kearny, NJ | 2 |
A ZIP code and an area code are unrelated systems. A ZIP code can sit in more than one area code, and an area code spans many ZIP codes.
Complaints on file for 551 numbers
1,366 FCC complaints are on file for 997 numbers in 551, most often filed as "Unwanted Calls". These are unverified consumer reports.
| Year of latest complaint | Numbers |
|---|---|
| 2023 | 81 |
| 2024 | 85 |
| 2025 | 78 |
Other area codes in New Jersey
New Jersey is one state with 10 area codes in the NANPA table. 551 is one of them.
Next to 551 in the numbering table
These are the codes just before and after 551 when all are sorted by number. They are neighbours on the list, not necessarily on the map.
What the area code does and does not tell you
A number that starts with 551 was first assigned in New Jersey. That is a fact about where the number began, and it is a useful hint when you check a form entry, for example a billing address in New Jersey next to a 551 phone number.
It does not show where the person is today. A number stays with its owner after a move or a change of provider (number portability), and mobile numbers travel with the handset. The area code also cannot tell you whether the line is active, who the carrier is, or whether the number is mobile or fixed: the plan shares those ranges. Read more about the area code, the numbering plan and line type.
Check numbers in bulk with the API
| Product | Credits | Docs |
|---|---|---|
| Phone Numbering-Plan Validation | 1 credit per valid number | API docs |
| Phone Intelligence (carrier and line status) | 1 credit per check (invalid numbers outside the US and Canada are free) | Product page |
Questions about area code 551
Where is area code 551?
NANPA assigns area code 551 to New Jersey, United States.
In which state does area code 551 sit?
New Jersey. 551 is one of 10 area codes the NANPA table assigns to the state.
Which places does area code 551 cover?
The places with the most ZIP codes among the rate centers in 551 are Jersey City, NJ, Hackensack, NJ and Kearny, NJ. The rate center list on this page shows all of them.
Who owns area code 551?
NANPA assigns area codes. Within 551, Omnipoint Communications holds the most prefixes, 67 prefixes or 23%.
Which time zone does 551 use?
The NANPA NPA report lists the time zone for 551 as Eastern (E).
What year did 551 enter service?
The NANPA NPA report gives an in-service date of 2001-12-29, so 551 has been in use since 2001.
Does area code 551 have an overlay?
Yes. 201 (in service 1947-01-01) shares the same area with 551, so numbers from all of them are local to each other.
Which area codes are nearest to 551?
The area codes closest to 551, measured between the centers of the ZIP code places they serve, are 862 (about 13 miles), 973 (about 13 miles), 908 (about 31 miles), 914 (about 34 miles) and 732 (about 38 miles).
How many prefixes does area code 551 have?
NANPA's report dated 2026-10-17 lists 294 prefixes in service in 551, spread over 23 rate centers and 29 holders.
Are there complaints about 551 numbers?
The FCC data on file has 1,366 complaints for 997 numbers in 551. They are unverified consumer reports. A number with no complaints on file is not proven safe.
Area code assignments: North American Numbering Plan Administrator NPA report, file dated 10/17/2026, retrieved 2026-10-17. Source file. New codes are assigned several times a year. Prefixes, rate centers, holders, time zone, in-service date and overlays: NANPA central office code report dated 2026-10-17 and NPA report dated 2026-10-18. Complaints: FCC consumer complaints open data, fetched 2026-10-17. ZIP code places: Postal code places and coordinates: GeoNames (geonames.org), licensed CC BY 4.0.