320
Area code

MN

United States geographic area code, in service since 1996-03-17.

Split from 612.

Statusin service
Introduced1996-03-17
JurisdictionMN, US
Local dialing7D
Time zoneCentral
Last verified2026-09-17
Utilization 67.6% of assignable prefixes assigned As of 09/17/2026
0%535 of ~792 assignable NXX values (200–999 excl. N11)100%

Prefix-level assignment does not equal number-level exhaustion; thousands-block pooling extends capacity. First assignment on record 2001-02-05, most recent 2026-09-14.

Area codes serve rate-center geographies, not municipal boundaries. “MN” identifies the jurisdiction, not an exact city footprint.

Top assignees

Ranked by assigned prefixes · initial assignee ≠ current carrier
Largest initial assignees in area code 320
RankAssigneePrefixesShare
01 ONVOY, LLC - MN 58 10.8%
02 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MN 57 10.7%
03 QWEST CORPORATION 42 7.9%
04 NEW CINGULAR WIRELESS PCS, LLC - IL 28 5.2%
05 CITIZENS TELECOM CO MN-FRONTIER CITIZENS COM-MN 27 5%
06 CENTURYLINK OF MINNESOTA, INC. 24 4.5%
07 LEVEL 3 COMMUNICATIONS, LLC - MN 23 4.3%
08 AERIAL COMMUNICATIONS, INC. 22 4.1%
09 FRACTEL, LLC 17 3.2%
10 MCC TELEPHONY OF MINNESOTA, LLC - MN 15 2.8%

Important: these are initial assignees from NANPA CO-code records — the carrier a prefix was originally assigned to. Because of number portability, the current serving carrier of any individual number may differ.

Change history

Recorded events for this NPA
  • 1996-03-17Area code 320 entered service (created from 612).

Planning letters & orders

Primary documents
NANPA planning letters for area code 320
DateDocumentSubject
1996-01-30 IL-96-01-017 ↗ REVISIONS TO THE SPLIT OF 612 (MINNESOTA) NUMBERING PLAN AREA (NPA)
1995-09-15 IL-95-09-007 ↗ NANP-SPLIT OF 612 (MINNESOTA) NUMBERING PLAN AREA (NPA)

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