Area code 450 vs 579
450 and 579 are overlay codes: they cover the same ground in Quebec, and a number in one is a local call to the other. 450 is the original, in service since 1998. 579 was added in 2010 because the first was filling up – that is what an overlay is for. Today 450 has 775 of 800 blocks assigned (96.9%) and 579 has 645 of 800 (80.6%), so a new number in the area now almost always comes from 579. In the 33 days to 30 October 2026, 450 drew 345 FTC complaints against 195 for 579 – 281st and 344th of 422 ranked codes. Older codes are spoofed more because they look more established. Neither code is better or safer than the other. They are the same geography, the same carriers and the same dialing rules; the difference is only how long each has existed and how full it is.
Side by side
| 450 | 579 | |
|---|---|---|
| In service since | 1998 | 2010 |
| Region | Quebec | Quebec |
| Blocks assigned | 775 of 800 (96.9%) | 645 of 800 (80.6%) |
| Largest block holder | Other CLEC / VoIP 15.6% | Other CLEC / VoIP 26.4% |
| Complaints, 28 Sep – 30 Oct 2026 | 345 (#281) | 195 (#344) |
| Rate centers | 130 | 126 |
Block share is allocation by the numbering administrator, not subscribers. Complaint counts cover 28 Sep – 30 Oct 2026 and measure how often each code is spoofed on caller ID.
Frequently asked
What is the difference between area codes 450 and 579?
None geographically – they overlay the same area, so the difference is age and how many numbers are left.
Do I need to dial the area code between 450 and 579?
Yes. Overlay areas use ten-digit dialing for local calls, including between the two codes. Seven digits reaches a recording.
Will a new number be 450 or 579?
Whichever has blocks left – currently 579, at 80.6% allocated against 96.9% for the other. Carriers draw from the code with free blocks, which is why the newer code spreads over time.
Is 450 or 579 more likely to be a spam call?
On the complaint data, 450 appears more often. But spoofing drives those counts, so this is about which code gets imitated, not which numbers are real.
Sources
- NANPA – NPA Database (npa_report.csv), file date 11/01/2026, retrieved Nov 1, 2026
- Canadian Numbering Administrator – CO Code Status, data date 2026-10-31, retrieved Nov 1, 2026
- FTC – Do Not Call Reported Calls Data, 28 Sep – 30 Oct 2026, retrieved Nov 1, 2026
Each code on its own: 450 · 579. All codes in Quebec: Quebec area codes.