331 area code: location, overlays and numbers
In Chicago, Illinois, the US telephone area code 331 has served since 2007 and shares an overlay with 630.
- Location
- Chicago, Illinois
- Service start
- 2007
- Local time zone
- Central time
- Overlay
- 630
- Local calling
- Dial 1 plus the 10-digit number
- Rate centre list
- 25
- Expected exhaust
- 2080
- The country code
- +1 (United States)
Based on NANPA public reports: area code report, rate-centre report, file dated 11/01/2026. The exhaust year comes from NANPA projections 2026-1 (April 2026). We are not an official NANPA site.
Get a number in the 331 area code
There are two routes to a 331 number. With its plan, a provider assigns a new number selected at sign-up from its holdings in the code. Sellers post numbers they already hold, often with a pattern, at a one-time price, and afterwards you move that number to a provider.
Providers listed by first-year cost
| Provider | Cheapest plan | First year | Link |
|---|---|---|---|
 Free app | Basic (Just for me), free | $0 | Open Google Voice |
 Free app | Free plan, free | $0 | Open TextNow |
 Developer API | Pay-as-you-go local number, $1.15 a month | $13.80 | Open Twilio |
 Second-number app | Standard, $3.99 a month billed yearly | $47.99 | Open Burner |
 Toll-free specialist | Solo, $6.99 a month billed yearly | $84 | Open UniTel Voice |
 Second-number app | Deluxe (local number), $6.99 a month billed yearly | $102.88 | Open GoDaddy Conversations (formerly Smartline) |
Sellers that list local numbers
| Seller | What it sells | Listed price | Monthly fee | Link |
|---|---|---|---|---|
 Marketplace | Local numbers | From $9 one-time | None stated | Search at Exclusive Digits |
 Marketplace | Local and toll-free | From $9.95 one-time | $2.99 a month | Search at NumberBarn |
 Number broker | Local and toll-free | From $99 one-time | None stated | Search at RingBoost |
 Number broker | Local and toll-free | From $100 one-time | None stated | Search at PhoneNumberExpert |
| 212areacode.comNumber broker | Local numbers | From $150 one-time | None stated | Search at 212areacode.com |
Some sellers and providers may pay us a referral fee. First-year cost determines the order, which never changes. How we earn
Places in the 331 area code
For 331, NANPA lists 25 rate centres. Numbers are assigned to each one, a local calling area:
Bartlett, Saint Charles, Aurora, Kaneville, Warrenville, Big Rock, Itasca, Wheaton, Batavia, Glen Ellyn, Plano, Downers Grove, Hinsdale, Sugar Grove, Elburn, Lemont, Lombard, Yorkville, Bensenville, West Chicago, Roselle, Geneva, Naperville, Elmhurst, Oswego.
Other related area codes
One area, one pool of numbers: 630. Any of these codes can give you a new number here, so request whichever one you want.
Illinois also has these area codes: 217, 312, 618, 815 and 309, 708, 847, 773 and 224, 779, 872, 447, 464, 861 and 730.
331 area code questions
What area does area code 331 serve?
Calls to 331 ring in Chicago, Illinois, near Chicago-Naperville-Elgin, IL-IN.
Which country code does a 331 number use?
+1. Since 331 belongs to the North American Numbering Plan, from abroad you dial +1 331 along with the 7-digit number.
What time is it in the 331 area code?
331 stays on Central time.
Who calls using a 331 number?
This code is used by homes, mobiles, local businesses and callers who use a fake local number. A 331 number displayed on your screen indicates its assigned location, not the identity of the caller.