The 507 area code is southern Minnesota, the full width of it — Rochester, Mankato, Winona, Austin, Albert Lea, Owatonna, Faribault, Northfield, Worthington, Fairmont, New Ulm, and Marshall — in service since January 1, 1954, and sharing its entire territory with the 924 overlay since August 30, 2024.
An unfamiliar 507 call is usually routine southern Minnesota — a clinic, a school office, a co-op returning a call — though the area code only says where the number was issued, never who is dialing it.
The 507 rundown
| In short | 507 |
|---|---|
| On the job since | January 1, 1954 — Minnesota’s third area code, after 1947 originals 218 and 612 |
| Parent | Carved from 612, which then held the state’s southeastern share |
| Second code | 924, same footprint, in service August 30, 2024 under Planning Letter PL-616 |
| Territory anchors | Rochester, Mankato, Winona, Austin, Albert Lea |
| Dialing plan | Ten-digit local calls since July 30, 2024; 1 + ten digits on toll calls |
| Supply outlook | Over 100 years — NANPA’s April 2026 analysis no longer prints a date |
One band of Minnesota, prairie to bluff country
Read NANPA’s rate-center map for the overlay left to right and you cross the whole state: Pipestone and Luverne against the South Dakota line, then Marshall, Worthington, Windom, and Fairmont over the prairie, the Minnesota River towns of New Ulm, St. Peter, and Mankato, the I-35 stops at Faribault, Owatonna, and Albert Lea with Northfield’s two colleges just east, and finally Rochester, Austin, and the Mississippi bluffs at Winona and La Crescent. Iowa runs beneath all of it.
Every one of those communities keeps Central Time and still opens its phone numbers with the digits it drew in the Eisenhower administration — 924 waits in reserve until 507’s own prefix inventory runs dry. Rochester, home of the Mayo Clinic, anchors the eastern end and supplies much of the code’s calling volume; Mankato’s state university anchors the middle.
The 1954 line that never moved
Minnesota entered the numbering plan on January 1, 1947 holding two codes: 218 wrapped across the north and west, 612 held the southeastern share, Twin Cities included. Seven years later, on January 1, 1954, the southern band got its own — NANPA’s database records 507 in service that day, the state’s first new code after the original map and its third overall.
What makes 507 unusual is everything that didn’t happen next. Each later Minnesota relief project carved 612 instead: 320 took the central counties in 1996, 651 took St. Paul in 1998, and 763 and 952 took the suburbs in 2000 — all four list 612 as their parent in NANPA’s records. The 1954 boundary around the south has outlasted them all untouched.
Why is 924 turning up in 507 country?
Because the old pool finally ran low. The forecast-history columns in NANPA’s current exhaust report tell it plainly: the October 2023 study projected 507 emptying in the first quarter of 2025, and the April 2024 study said the second quarter — months of runway, not years. Relief had to arrive first.
It did. On April 6, 2023, the Minnesota Public Utilities Commission approved an all-services distributed overlay in Order No. P-999/M-22-461, and NANPA scheduled it in Planning Letter PL-616 that June. An overlay adds a second code to the same map without renumbering anyone — the modern default remedy, as our area code explainer lays out — and 924 entered service on August 30, 2024, the first overlay Minnesota has ever had, though not one 924 prefix has been handed out yet.
One clause makes this overlay rarer than most: PL-616 holds 924’s central office codes back until every assignable 507 code is taken. Virginia wrote the same waiting rule into 826 over 540; in both places, the new code’s numbers are issued only after the old inventory truly runs out.
Ten digits after seventy years
The dialing change came ahead of the new code. Permissive ten-digit dialing opened January 30, 2024, and at the July 30, 2024 cutover it became mandatory — a local call anywhere in the 507/924 territory now takes all ten digits, toll calls take 1 plus ten, and carriers may accept 1 plus ten locally at their discretion. Carriers validated routing against a test number that could only belong to this project, 924-924-1924, live from May 30 through September 30, 2024.
Notably, the 988 crisis-line conversions never touched this code. Planning Letter PL-556 (January 8, 2021) pushed 82 area codes onto ten-digit dialing, and Minnesota’s entries were 218 and 952 — not 507. So seven-digit dialing here survived the 988 launch by two full years and fell to the overlay instead, seventy years after the code went live.
A runway too long to print
NANPA’s April 2026 exhaust analysis carries 507/924 with a footnote instead of a date: forecasted exhaust is more than 100 years in the future, so no year or quarter is provided. The climb is steep in the report’s own history — second quarter of 2084 in the October 2024 study, fourth quarter of 2103 by April 2025, third quarter of 2118 by October 2025, and now off the table entirely.
July 6, 2026 brought revisions to four Texas entries and to nothing in Minnesota, and NANPA’s mid-August 2026 database has 507 out of jeopardy with relief planning nowhere on file. A code that had two quarters of paper runway in 2024 now has more than a century — the arithmetic of fresh NXX prefixes, doubled at a stroke.
A 507 display, and what stands behind it
In small-metro and rural markets, an out-of-area number gets screened hard, and the answer-rate gap between strange digits and hometown digits is real money on an outbound campaign — our local presence dialing guide walks through the numbers. Across this footprint, one code covers every market from Pipestone to Winona, so a single set of local digits works the entire southern band of the state.
The digits alone are not identity, however — caller ID spoofing can plant 507 on a call from anywhere, which is why the durable signal is the cryptographic one applied at the carrier. SIPNEX operates under a direct FCC license and signs outbound traffic at A-level attestation with its own STIR/SHAKEN certificate — provenance a spoofed display cannot supply.
The supply side is straightforward: SIPNEX provisions local DID numbers town by town — Rochester, Mankato, and the rest as inventory allows — and delivers them into any PBX or dialer over SIP trunking, with toll-free available through the company’s own RespOrg registration when a campaign needs both.
507, point by point
Which southern Minnesota cities carry 507 numbers?
Rochester, Mankato, Winona, Austin, Albert Lea, Owatonna, Faribault, Northfield, Worthington, Fairmont, New Ulm, and Marshall are the biggest names on the map. The code spans Minnesota’s entire southern band — from Pipestone and Luverne at the South Dakota line to La Crescent on the Mississippi, with Iowa along the bottom edge — all on Central Time, and all shared with the 924 overlay since August 30, 2024.
Is 924 the same region as the 507 area code?
Yes — 924 is an overlay covering exactly the territory 507 covers, in service since August 30, 2024. Under the Minnesota PUC’s April 6, 2023 order and NANPA Planning Letter PL-616, new 924 prefixes may be assigned only once the last assignable 507 prefix is claimed, so the first 924 numbers will appear only after 507’s remaining inventory is spent. No existing 507 number changed.
When did the 507 area code stop dialing seven digits?
At the July 30, 2024 cutover, when ten-digit dialing became mandatory ahead of the 924 overlay’s launch. Permissive ten-digit dialing had run since January 30, 2024 under PL-616. 507 never appeared on PL-556 — the 2021 list of 82 codes converted for the 988 crisis line named Minnesota’s 218 and 952 — so its seven-digit habit lasted seventy years, from January 1, 1954 until the overlay ended it. Toll calls take 1 plus ten digits.
How close did the 507 area code come to running out of numbers?
Within about two quarters, on paper — NANPA’s October 2023 and April 2024 studies both projected exhaust in early-to-mid 2025. The 924 overlay landed first, and the forecast reversed: 2084 in the late-2024 study, 2118 by October 2025, and the April 2026 analysis now lists exhaust as more than 100 years out, no date printed. The revisions of July 6, 2026 reached four Texas complexes only.
Can a company outside Minnesota run a 507 area code number?
Yes. Local numbers follow rate-center assignment, not street addresses, so 507 digits can ring desks in any state over SIP. SIPNEX issues local DID numbers one exchange at a time — Rochester, Mankato, Winona, and the rest where inventory permits — and routes them into whatever phone system already answers, under its own FCC carrier authorization.
Southern Minnesota picks up quickest for its own three digits. SIPNEX stocks 507 rate-center numbers under a direct FCC license, hands them off over dialer-grade SIP, and signs every outbound leg at A-level on its own certificate — rates are published, the contact desk reads every note, and (833) 665-2220 gets a human answer.
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