Area codes · +1
Area code 773
Area code 773 covers Chicago. We hold 5,375 allocated blocks for it across 11 rate centres, split 51% mobile, 42% landline and 7% VoIP.
The other area codes laid over 773
Area code 773 does not have Chicago to itself. 2 other codes — 312, 872 — serve the same rate centres, laid over the same ground rather than dividing it. That is an overlay: a new code added when the old one ran out of numbers, covering the same streets. Two neighbours can hold different area codes, so the code says roughly when a number was issued rather than where it sits.
Each holds its own blocks and its own carrier mix, so a 773 number and a 312 number from the same street can report different line types. Filtering Chicago by area code needs all 3 of them.
773 is not confined to Chicago itself: its blocks sit across 11 rate centres, named in the table below.
Illinois is split across 17 area codes — 224, 618, 708, 815, 217, 773 and others. By allocated blocks 773 is the 7th largest of them, holding 8% of the Illinois total.
Where 773 numbers are concentrated
Rate-centre names are reproduced as NANPA records them. The agency truncates them to ten characters, so longer names appear shortened elsewhere on this site.
| Rate centre | Blocks | Share of 773 |
|---|---|---|
| Chicago | 1,419 | 26% |
| Chicago | 647 | 12% |
| Chicago | 592 | 11% |
| Chicago | 499 | 9% |
| Chicago | 455 | 8% |
| Chicago | 426 | 8% |
| Chicago | 332 | 6% |
| Chicago | 331 | 6% |
| Chicago | 305 | 6% |
| Chicago | 179 | 3% |
| Chicago | 176 | 3% |
Carriers holding the most 773 blocks
T-Mobile Usa, Inc.1,149 blocks
Illinois Bell792 blocks
T-Mobile USA, Inc.628 blocks
AT&T Wireless439 blocks
Verizon Wireless350 blocks
Bandwidth309 blocks
The largest holder, T-Mobile Usa, Inc., has 21% of the code.
These are original allocations. A number keeps its digits and its block when its subscriber moves network, so a ported 773 number still reports the carrier it started with. Closing that gap needs a live query against the routing database. How line type is derived.
Check a single 773 number, or run a whole list through the free cleaner — neither uploads anything.
Common questions
Where is area code 773?
Area code 773 covers Chicago. It is not the only code there: 312, 872 are overlays on the same rate centres, so a Chicago number can start with any of them.
Is a 773 number a mobile or a landline?
It can be either, and the digits do not say which. North American mobile and landline numbers share the same ranges, so the answer comes from the carrier holding the block. In 773 the split runs 51% mobile, 42% landline and 7% VoIP, so mobile is the most likely single answer.
Which carriers hold 773 numbers?
The largest holders are T-Mobile Usa, Inc., Illinois Bell, T-Mobile USA, Inc.. That is the carrier the block was allocated to, which is not necessarily the network a given number sits on today.
How many 773 numbers are there?
The code holds 5,375 allocated blocks in our copy of the numbering plan. A block is 1,000 or 10,000 consecutive numbers depending on how deeply it has been pooled, so 773 covers on the order of 5,375,000 possible numbers — most of which have never been issued to anyone.