Real 312 — The 312 area code and Chicago-region | real312.com
The number itself is always ten digits; only the prefix changes with where you dial from.
First, know what you are dialling. A US number is a 3-digit area code, a 3-digit central-office code and a 4-digit line number, written 312-555-0100. The digit 1 is the long-distance prefix, not part of the number.
From a US mobile: dial the ten digits straight — 312 plus the seven-digit subscriber number — and press call. Mobile networks route on the full national number, so no prefix is needed and seven digits alone will not complete.
From a US landline: if the call is long distance, dial 1, then 312, then the seven-digit number. If you are inside an overlay region, remember the local rule — seven-digit dialling ended when the overlay went live, so even a call across the street takes ten digits.
On narrow screens, swipe or scroll the plate sideways.
From outside the United States: dial your country's exit code, then country code 1, then 312 and the seven-digit number. From the UK the complete string is 00 1 312 followed by the seven digits; other countries substitute their own exit code for the 00.
On a VoIP line: because VoIP is not anchored to a physical exchange, treat every call as out-of-area. Dial the full ten digits, or the international form beginning with country code 1 if your provider formats numbers that way.
Three failures account for most misdials: leaving the 1 off a landline long-distance call, dialling seven digits in overlay territory, and dropping the exit code on an international call. If a call does not complete, check those three in order — and if you are unsure which code an address belongs to, confirm it on the code-map page first.
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