Area code 602 opened in January 1947 as the first area code in Arizona. Splits created 520 in 1995 and 480 and 623 in 1999. Since 2023, 480, 602, and 623 have worked as one boundary elimination overlay across the Phoenix area.
Quick answer
- 602 opened in January 1947 (FCC) and today serves the majority of the City of Phoenix (NANPA).
- 520 opened in March 1995, and 480 and 623 opened in March 1999 (FCC).
- The Arizona Corporation Commission approved a boundary elimination overlay on November 9, 2021. The combined 480/602/623 area began service September 12, 2023 (NANPA).
- Local calls require ten digits, mandatory since August 12, 2023 (NANPA).
- Arizona stays on Mountain Standard Time all year (Arizona law and NIST).
The essentials
602 area code: quick facts
| Area code | 602 |
| Coverage | The majority of the City of Phoenix, part of Glendale, Cave Creek, and Ahwatukee, within the shared 480/602/623 overlay area |
| State | Arizona |
| Time zone | Mountain Standard Time all year; Arizona does not observe daylight saving time |
| Assigned | January 1947, the earliest Arizona code in the FCC list |
| Codes opened after 602 | 520 (March 1995), 480 and 623 (March 1999), 928 (June 2001) |
| Overlay | 480/602/623 boundary elimination overlay, approved November 9, 2021; in service September 12, 2023 |
| Dialing | 10 digits for local calls: 3-digit area code plus 7-digit number |
How 602 became Phoenix's code
- January 1947: The FCC lists area code 602 as opened for Arizona. It is the earliest Arizona code in the FCC table; the next one listed opened in 1995. Wikipedia says 602 covered the whole state until then; that is not confirmed by the regulator.
- March 1995: Area code 520 opens (FCC). Wikipedia gives the in-service date as March 19, 1995, with metro Phoenix keeping 602. The FCC table gives only the month.
- November to December 1998: Per Wikipedia only, the Arizona Corporation Commission first voted for an overlay in November 1998, then reconsidered and approved a three-way split on December 18, 1998. The regulator and NANPA sources checked do not cover this step.
- March 1999: Area codes 480 and 623 open (FCC). Wikipedia says the effective date was March 1, 1999, with 480 serving most of the East Valley, 623 most of the West Valley, and 602 keeping most of Phoenix.
- June 2001: Area code 928 opens in Arizona (FCC).
- November 9, 2021: The Arizona Corporation Commission, in Docket No. T-00000A-21-0187, Decision No. 78311, approves a boundary elimination overlay as the relief method for the 480 area code (NANPA Planning Letter PL-576).
- February 11, 2023: Permissive 10-digit dialing starts in 602 and 623 (NANPA). The 480 code already used 10-digit local dialing.
- August 12, 2023: Mandatory 10-digit dialing begins (NANPA).
- September 12, 2023: The in-service date of the combined 480/602/623 overlay, and the earliest date central office codes of any of the three can be effective throughout the combined area (NANPA).
Where area code 602 is used
NANPA's December 2021 planning letter describes 602 as serving "the majority of the City of Phoenix as well as, but not limited to, a portion of the City of Glendale, and the communities of Cave Creek and Ahwatukee." The same letter says 480 serves southcentral Arizona and 623 serves Glendale and West Valley communities. It gives counties only for 480 (Maricopa and Pinal), not for 602.
Wikipedia's account of the 1999 boundaries places Ahwatukee outside 602, while the 2021 NANPA letter lists it under 602. The sources checked do not explain the difference. Since the boundary lines were removed in 2023, the code no longer shows which part of the area a number belongs to, so confirm a specific address with your phone provider.
Why 602 needed relief
NANPA's letter says the overlay was approved "as the relief method for the 480 NPA," the code whose numbers were running low. The letter does not give a supply forecast. Wikipedia, citing NANPA, says a forecast made in October 2020 expected 480 to run out in the first quarter of 2024 and 602 in 2026, with 623 not expected to run out until 2069. These figures come from Wikipedia and are not confirmed by the regulator.
This was not Phoenix's first attempt at relief. Per Wikipedia, NANPA declared jeopardy procedures in 1998, and the Commission's overlay vote that year was reversed in favor of the 1999 split. A boundary elimination overlay differs from either: it does not add a new code or move any boundary. Instead, NANPA says central office codes from 480, 602, or 623 can now become effective throughout the whole combined area.
Neighboring area codes in Arizona
The table shows how each Arizona code relates to 602, based on the FCC and NANPA sources in this guide.
| Code | Where it applies | Relation to 602 |
|---|---|---|
| 602 | Majority of the City of Phoenix, part of Glendale, Cave Creek, Ahwatukee | Opened January 1947 |
| 480 | Southcentral Arizona: part of Phoenix, Chandler, Gilbert, Mesa, Tempe, Scottsdale, Sun Lakes (Maricopa and Pinal counties) | Opened March 1999; same overlay area since 2023 |
| 623 | Glendale, Avondale, Tolleson, Buckeye, Sun City, New River | Opened March 1999; same overlay area since 2023 |
| 520 | Outside the Phoenix overlay area on the NANPA map; the sources checked do not describe its cities | Opened March 1995 |
| 928 | Outside the Phoenix overlay area on the NANPA map; the sources checked do not describe its cities | Opened June 2001 |
The 480/602/623 boundary elimination overlay
A boundary elimination overlay keeps the three existing codes but removes the geographic lines between them. NANPA says the new 480/602/623 overlay "will service the same geographic area currently served by the 480, 602 and 623 NPAs."
| Step | Date |
|---|---|
| Commission approval | November 9, 2021 (Decision No. 78311) |
| Permissive 10-digit dialing starts (602 and 623) | February 11, 2023, 12:01 AM MT |
| Mandatory 10-digit dialing | August 12, 2023, 12:01 AM MT |
| Earliest date central office codes ordered through NANPA | July 8, 2023 |
| Overlay in service | September 12, 2023 |
Some secondary sources give November 2, 2021 for the Commission decision. NANPA's planning letter, which cites the docket and decision number, says November 9, 2021, and this guide uses that date. The Arizona Corporation Commission's own page could not be opened for this review.
Time zone and daylight saving time
Arizona is different from most of the country. Arizona Revised Statutes section 1-242 sets Arizona's standard time as mountain standard time and says the state "elects to reject" daylight saving time. The legislature can change that by future action. NIST says daylight saving time is not observed in Arizona, "with the exception of the Navajo Indian Reservation, which does observe DST." The IANA time zone data lists America/Phoenix as "MST - AZ (except Navajo)" and America/Denver as "Mountain (most areas)."
For Phoenix this means no clock change. In 2026 most of the country moves on March 8 and November 1 (NIST), but Phoenix stays on Mountain Standard Time. As a result, Phoenix clocks match Mountain Time in winter and match Pacific Time in summer. The sources checked do not place the Navajo Nation inside the 480/602/623 area, so that exception is outside the scope of this guide. Anyone scheduling calls across the year should check the other party's time zone each season.
How to dial a 602 number
The FCC says calls between area codes are generally dialed with the three-digit area code followed by a seven-digit local number. In the 480/602/623 overlay area, NANPA's dialing plan is: 10 digits for local calls, 1 plus 10 digits for toll calls, and 0 plus 10 digits for operator-assisted calls. NANPA adds that 1 plus 10 digits for local calls is permitted at each provider's discretion.
Before August 12, 2023, 602 and 623 callers could still dial seven digits for calls inside the area during the permissive period. That period has ended.
Caller ID and scams with a 602 number
The FTC warns that "Scammers can make any name or number show up on your caller ID. That's called spoofing." Scammers can also match the first six digits of your own number. The FTC calls this neighbor spoofing.
- If you pick up and do not recognize the caller, the FTC advises that you hang up.
- Letting an unknown call go to voicemail is one option.
- The FTC says call blocking is your best defense against unwanted calls.
A 602 number shows the code that was assigned, not who is calling or where they are. Because 480 and 623 share the same area, a 602 caller ID is not a reliable sign that the caller is in Phoenix.
Business numbers in the Phoenix area
Since September 12, 2023, central office codes from 480, 602, or 623 can be effective anywhere in the combined area (NANPA). A business in Phoenix, Mesa, or Glendale can therefore hold a number from any of the three codes, and two offices on the same street can have different area codes. The sources checked do not say which code a new line will receive.
Because the codes share one area, route calls by team or extension, not by area code. Ask your provider which code a new line gets, since that depends on its current inventory.
Whether a specific 602 number can be assigned to your business depends on your phone provider and its current inventory. This guide does not make claims about availability.
Important: Confirm availability with your provider before you plan a campaign or print a number on materials.
Before you use a 602 number
- Confirm the number is available from your provider, and get its terms in writing.
- Ask who owns the number and whether it can be moved to another provider if you switch.
- Confirm which area code your line uses. 480, 602, and 623 all serve the same combined area.
- Set 10-digit dialing for local calls in phones, dialers, and forms before you go live, because NANPA says 10 digits are mandatory in the overlay area.
- Route calls by team or extension, because 602 and its neighbors share one territory.
- Check each site's address with your provider. The sources checked do not give a street-level boundary for any of the three codes.
- Plan for time zones. Phoenix stays on Mountain Standard Time all year, so scheduling with other regions changes in summer.
- Plan for caller ID. A 602 number does not prove who is calling, and neighbor spoofing copies the first six digits of your own number.
Frequently asked questions
Which area is the 602 area code for?
Area code 602 serves Phoenix, Arizona. NANPA says it serves the majority of the City of Phoenix, a portion of Glendale, and the communities of Cave Creek and Ahwatukee. The FCC lists 602 as opened in January 1947. Since the boundary elimination overlay, 602 shares the same geographic area with 480 and 623.
Is area code 602 being split or replaced?
No new split of 602 appears in the official sources checked for this guide. The Arizona Corporation Commission approved a boundary elimination overlay for 480, 602, and 623 on November 9, 2021 (Decision No. 78311, per NANPA), and the overlay area began service on September 12, 2023. Future relief plans could not be verified.
Do I need to dial 10 digits for a 602 number?
Yes. NANPA says that after the permissive period ended on August 12, 2023, local calls in the 480/602/623 overlay area must be dialed with 10 digits. Toll calls use 1 plus 10 digits. Confirm the dialing rules for calls outside the area with your phone provider.
What time zone is area code 602 in, and does it observe daylight saving time?
Arizona state law sets standard time as mountain standard time and rejects daylight saving time (Arizona Revised Statutes 1-242). NIST says DST is not observed in Arizona, except on the Navajo Indian Reservation. Phoenix clocks stay on Mountain Standard Time all year.
Does a 602 number mean the caller is in Phoenix?
Not always. The FTC says scammers can make any name or number show up on caller ID, and neighbor spoofing uses numbers that match the first six digits of your own. Also, NANPA says the 480, 602, and 623 codes now serve the same combined area, so the code alone does not show which part of the Phoenix area a number belongs to.
What is the difference between 602, 480, and 623?
Per NANPA, 602 serves the majority of the City of Phoenix, 480 serves southcentral Arizona communities such as Chandler, Gilbert, Mesa, Tempe, and Scottsdale, and 623 serves Glendale, Avondale, Tolleson, Buckeye, Sun City, and New River. The FCC lists 480 and 623 as opened in March 1999. Since the 2023 overlay, the three codes serve the same combined area.
Sources · reviewed October 2026
NPA 480, 602 and 623 Boundary Elimination Overlay, NANPA Planning Letter PL-576 (December 30, 2021) and archived copy
Used for the Commission approval date, docket and decision number, the descriptions of where 480, 602, and 623 serve, the overlay dates, and the dialing plan. The live NANPA address returned an access error during review; the text was read from the archived copy.
Numbering Resource Utilization in the United States, FCC (December 2024), Tables 6 and 29
Used for the opening dates of 602 (January 1947), 520 (March 1995), 480 and 623 (March 1999), and 928 (June 2001), and for the three-digit area code plus seven-digit number format.
Area codes 602, 480, and 623, Wikipedia
Weak source, used only where no official page was reachable: the statewide coverage before 1995, the March 19, 1995 and March 1, 1999 dates, the 1998 overlay vote and December 1998 split approval, the 1999 boundary descriptions, and the October 2020 exhaustion forecast. These are not confirmed by the regulator.
Arizona Revised Statutes 1-242, Standard time, Daylight Saving Time, NIST, and tz database zone table
Used for Arizona's mountain standard time and rejection of daylight saving time, the Navajo Indian Reservation exception, the 2026 change dates for the rest of the country, and the America/Phoenix and America/Denver zone labels.
Phone Scams, FTC Consumer Advice and That's not your neighbor calling, FTC Consumer Alert
Used for the spoofing definition, the neighbor spoofing explanation, the advice to hang up on unknown callers, the voicemail option, and the call-blocking advice.