Phone prefixes in St-Chrysostome, QC

In numbers

In-service prefixes

6

Telephone numbers covered

60,000

Carriers

6

Area codes

2

Provinces and territories

1

First assignment

April 18, 2011

Most recent assignment

October 22, 2025

St-Chrysostome’s share of its area codes

Within area code 450, St-Chrysostome accounts for only 4 of 775 prefixes (0.5%): the code is dominated by Granby and spread over 129 rate centres. Within area code 579, St-Chrysostome accounts for only 2 of 644 prefixes (0.3%): the code is dominated by Granby and spread over 126 rate centres.

Who holds these numbers

Bell Canada holds the largest share at 1 prefixes, 16.7% of the total, ahead of 5 other carriers. Code by code: in 450, Bell Canada leads with 1 of 4 prefixes ahead of 3 others; in 579, Fibernetics Corporation leads with 1 of 2 prefixes ahead of 1 others. No carrier holds prefixes in every one of St-Chrysostome’s 2 area codes, while 6 appear in just one.

Wireless and wireline

None of St-Chrysostome’s holders carries a mobility brand in its registered name: all 6 prefixes belong to wireline or wholesale carriers, among them Bell Canada, Comwave Networks, Fibernetics Corporation and ISP Telecom Inc. A call showing a St-Chrysostome number therefore nominally comes from a landline, cable or VoIP platform rather than a locally assigned cellphone.

How the allocation was built up

St-Chrysostome’s dated assignments run from 2011 to 2025. The busiest period was 2010–2014, when 3 prefixes went to 3 carriers. 1 prefixes (17%) carry no date in the register: these are the historic pre-1999 assignments, the wireline bedrock of the rate centre. Since 2020 another 2 prefixes have been added, so the rate centre is still growing.

St-Chrysostome’s oldest prefixes, the ones the register leaves undated, belong to Bell Canada: this carrier made up the landscape before competition arrived. The first dated assignment went to ISP Telecom Inc. in 2011. The most recent arrivals are TELUS Quebec (2025), Fibernetics Corporation (2021) and Comwave Networks (2013), a sign that new carriers are still asking for numbers in St-Chrysostome.

St-Chrysostome has just 6 prefixes (60,000 numbers): a very small rate centre, typical of a village or rural area served by a single switching office.

No single carrier dominates St-Chrysostome: the leader, Bell Canada, holds only 16.7% of the prefixes against 5 competitors, a sign of a highly fragmented market where cable companies, mobility brands and VoIP providers weigh as much as the incumbent.

Demand remains steady: 40.0% of the dated prefixes go back to the last ten years, the most active period being 2010–2014. The rate centre is growing at a regular rather than explosive pace.

1 undated in the register.

Dialling a St-Chrysostome number

St-Chrysostome is served by 2 overlaid area codes (450 and 579). A 579 number is no more “out of town” than a 450 one; from abroad, dial +1 and the full ten digits.

The numbering neighbourhood

St-Chrysostome shares area codes 450 and 579 with at least 20 other rate centres, including Granby, Joliette, St-Jerome, St-Hyacinthe, Longueuil, Ste-Therese, Pont-Viau and Sorel. The largest of them, Granby, holds 51 prefixes in 450 and 579; the smallest on the list, Lachute, has just 17.

What a St-Chrysostome number tells you

A number attached to St-Chrysostome tells you that its prefix was issued to a carrier for this rate centre in Quebec, most often Bell Canada. It does not tell you where the handset is today: a subscriber may have ported the number to any of the 6 carriers present here or to a VoIP service usable anywhere. Nor does it tell you who is calling: caller ID can be spoofed, and a Quebec area code is easy to borrow to look local.

Reading a register entry for St-Chrysostome: code 450-826 is recorded for Bell Canada, so every 450-826-XXXX number (10,000 possible) descends from that assignment. “St-Chrysostome, Quebec” there names a rate centre, not a municipality, and several area codes overlay it.

Every St-Chrysostome prefix

Each row is an in-service central-office code recorded for St-Chrysostome, with its original holder and year of assignment.

Allocated prefixes

All 6 in-service prefixes, grouped by rate centre.

Elsewhere in Quebec