Area code
503
503 is a United States area code. Under the North American Numbering Plan it belongs to Oregon, which has 4 area codes in total.
Validate a number in 503
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 503 at a glance
NANPA lists 783 central office codes (prefixes) in use in area code 503, held by 39 holders across 63 rate centers.
| Fact | Value |
|---|---|
| In service since | 1947-01-01 |
| Time zone | Pacific (P) |
| Assigned overlays | 971 (2000-10-01) |
| Prefixes in use | 783 |
| Pooled prefixes | 366 (47%) |
| Rate centers | 63 |
| Companies holding prefixes | 39 |
| Assignment dates on file | 2001-05-08 to 2024-06-04 (85 prefixes) |
| ZIP codes in its places | 127 |
Rate centers in area code 503
The largest rate center is PORTLAND, with 347 prefixes (44%).
| Rate center | Prefixes | Share |
|---|---|---|
| PORTLAND | 347 | 44% |
| BEAVERTON | 107 | 14% |
| SALEM | 73 | 9% |
| CLACKAMAS | 49 | 6% |
| STFRD-SNDY | 28 | 4% |
| GRESHAM | 21 | 3% |
| MCMINNVL | 13 | 2% |
| DALLAS | 8 | 1% |
| 55 other rate centers | 137 | 17% |
Who holds the prefixes in 503
Qwest holds the most prefixes, 222 (28%). 47% of the prefixes are pooled, which means their thousands-blocks can belong to different companies.
| Holder | Prefixes | Share |
|---|---|---|
| Qwest | 222 | 28% |
| Ziply Fiber | 111 | 14% |
| New Cingular Wireless PCS | 71 | 9% |
| T-Mobile USA | 56 | 7% |
| Verizon Wireless | 54 | 7% |
| Allstream | 51 | 7% |
| 33 other carriers | 218 | 28% |
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 503
- 1947-01-01 Area code 503 went into service.
- 1995-11-05 Area code 541 went into service and names 503 as its parent.
- 2000-10-01 Area code 971 went into service as an overlay in the same area as 503.
Area codes nearest to 503
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 503
127 ZIP codes fall in places that have a rate center in this area code.
| Place | ZIP codes |
|---|---|
| Portland, OR | 60 |
| Salem, OR | 14 |
| Beaverton, OR | 10 |
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 503 numbers
4,154 FCC complaints are on file for 3,465 numbers in 503, most often filed as "Unwanted Calls". These are unverified consumer reports.
| Year of latest complaint | Numbers |
|---|---|
| 2023 | 200 |
| 2024 | 134 |
| 2025 | 135 |
Other area codes in Oregon
Oregon is one state with 4 area codes in the NANPA table. 503 is one of them.
Next to 503 in the numbering table
These are the codes just before and after 503 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 503 was first assigned in Oregon. 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 Oregon next to a 503 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 503
Where is area code 503?
NANPA assigns area code 503 to Oregon, United States.
In which state does area code 503 sit?
Oregon. 503 is one of 4 area codes the NANPA table assigns to the state.
Which places does area code 503 cover?
The places with the most ZIP codes among the rate centers in 503 are Portland, OR, Salem, OR and Beaverton, OR. The rate center list on this page shows all of them.
Who owns area code 503?
NANPA assigns area codes. Within 503, Qwest holds the most prefixes, 222 prefixes or 28%.
Which time zone does 503 use?
The NANPA NPA report lists the time zone for 503 as Pacific (P).
What year did 503 enter service?
The NANPA NPA report gives an in-service date of 1947-01-01, so 503 has been in use since 1947.
Does area code 503 have an overlay?
Yes. 971 (in service 2000-10-01) shares the same area with 503, so numbers from all of them are local to each other.
Which area codes are nearest to 503?
The area codes closest to 503, measured between the centers of the ZIP code places they serve, are 564 (about 99 miles), 360 (about 100 miles), 458 (about 108 miles), 541 (about 112 miles) and 253 (about 130 miles).
How many prefixes does area code 503 have?
NANPA's report dated 2026-10-17 lists 783 prefixes in service in 503, spread over 63 rate centers and 39 holders.
Are there complaints about 503 numbers?
The FCC data on file has 4,154 complaints for 3,465 numbers in 503. 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.