Phone prefixes in Field

In numbers

In-service prefixes

5

Telephone numbers covered

50,000

Carriers

5

Area codes

4

Provinces and territories

2

First assignment

May 9, 2016

Most recent assignment

March 22, 2024

Provinces and territories

This name is used for separate rate centres in 2 provinces. The prefixes below share a name in the CNAC register but belong to different communities.

• Ontario — 3 prefixes
• British Columbia — 2 prefixes

Field’s share of its area codes

Within area code 249, Field accounts for only 2 of 585 prefixes (0.3%): the code is dominated by Sudbury and spread over 176 rate centres. Within area code 236, Field accounts for only 1 of 730 prefixes (0.1%): the code is dominated by Vancouver and spread over 269 rate centres. Within area code 250, Field accounts for only 1 of 781 prefixes (0.1%): the code is dominated by Victoria and spread over 268 rate centres. Within area code 705, Field accounts for only 1 of 770 prefixes (0.1%): the code is dominated by Barrie and spread over 203 rate centres.

Who holds these numbers

Bell Canada holds the largest share at 1 prefixes, 20.0% of the total, ahead of 4 other carriers. Code by code: in 249, Fibernetics Corporation leads with 1 of 2 prefixes ahead of 1 others; Navigata Communications Limited is the only holder in 236; TELUS is the only holder in 250; Bell Canada is the only holder in 705. No carrier holds prefixes in every one of Field’s 4 area codes, while 5 appear in just one.

Wireless and wireline

None of Field’s holders carries a mobility brand in its registered name: all 5 prefixes belong to wireline or wholesale carriers, among them Bell Canada, Fibernetics Corporation, Navigata Communications Limited and TELUS. A call showing a Field number therefore nominally comes from a landline, cable or VoIP platform rather than a locally assigned cellphone.

How the allocation was built up

Field’s dated assignments run from 2016 to 2024. The busiest period was 2020–2024, when 2 prefixes went to 2 carriers. 2 prefixes (40%) 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.

Field’s oldest prefixes, the ones the register leaves undated, belong to Bell Canada and TELUS: these carriers made up the landscape before competition arrived. The first dated assignment went to Navigata Communications Limited in 2016. The most recent arrivals are TELUS Integrated Communications (2024), Fibernetics Corporation (2022) and Navigata Communications Limited (2016), a sign that new carriers are still asking for numbers in Field.

Field has just 5 prefixes (50,000 numbers): a very small rate centre, typical of a village or rural area served by a single switching office.

No single carrier dominates Field: the leader, Bell Canada, holds only 20.0% of the prefixes against 4 competitors, a sign of a highly fragmented market where cable companies, mobility brands and VoIP providers weigh as much as the incumbent.

Growth is recent: 66.7% of the dated prefixes were assigned in the last ten years, peaking in 2020–2024. Field is among the rate centres where demand for numbers is still rising quickly.

2 undated in the register.

Dialling a Field number

Field is served by 4 overlaid area codes (249, 236, 250 and 705). A 705 number is no more “out of town” than a 249 one; from abroad, dial +1 and the full ten digits.

The numbering neighbourhood

Field shares area codes 249, 236, 250 and 705 with at least 20 other rate centres, including Vancouver, Victoria, Barrie, Sudbury, Peterborough, Kelowna, Sault Ste. Marie and North Bay. The largest of them, Vancouver, holds 142 prefixes in 236; the smallest on the list, Bracebridge, has just 21.

What a Field number tells you

A number attached to Field tells you that its prefix was issued to a carrier for this rate centre in Ontario, 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 5 carriers present here or to a VoIP service usable anywhere. Nor does it tell you who is calling: caller ID can be spoofed, and an Ontario area code is easy to borrow to look local.

Reading a register entry for Field: code 705-758 is recorded for Bell Canada, so every 705-758-XXXX number (10,000 possible) descends from that assignment. “Field, Ontario” there names a rate centre, not a municipality, and several area codes overlay it.

Every Field prefix

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

Allocated prefixes

All 5 in-service prefixes, grouped by rate centre.

Elsewhere in Ontario