Iowa area codes
Iowa uses 5 area codes. The oldest is 319, in service since 1947; the newest is 563, from 2001. Across them 2,748 of 3,930 possible number blocks are allocated, 69.9% of capacity. Across the state no single national carrier holds the most blocks: 37.8% sits with CLEC and VoIP holders counted together, ahead of Lumen at 16.6%. In the 33 days to 30 October 2026, FTC complaints named an Iowa caller ID 2,515 times – 1.1% of all complaints in the window, most often 515 with 859 (76th of 422 nationally). NANPA records 811 rate centers across the state's codes.
All 5 codes
| Code | In service | Blocks used | Largest holder | Complaints | Shares area with |
|---|---|---|---|---|---|
| 319 | 1947 | 565/786 | Other CLEC / VoIP 38.8% | 543 | no overlay |
| 515 | 1947 | 578/786 | Other CLEC / VoIP 30.3% | 859 | no overlay |
| 563 | 2001 | 388/786 | Other CLEC / VoIP 39.2% | 352 | no overlay |
| 641 | 2000 | 584/786 | Other CLEC / VoIP 41.1% | 337 | no overlay |
| 712 | 1947 | 633/786 | Other CLEC / VoIP 39.8% | 424 | no overlay |
Block share is share of allocated number blocks, not of subscribers. Complaint counts cover 28 Sep – 30 Oct 2026 and reflect spoofed caller IDs as much as real calls.
How full Iowa’s codes are
A code holds at most 786 blocks of 10,000 numbers each. When a code fills up, the administrator does not reclaim numbers – it adds an overlay, and from then on new numbers in the same area come from the new code.
Who holds the number blocks
Counted from every assigned block in the state: 2,748 blocks, each with the holder NANPA recorded for it. Percentages are measured, not estimated.
| Holder | Blocks | Share of Iowa | Largest in |
|---|---|---|---|
| Other CLEC / VoIP | 1,038 | 37.8% | 5 codes |
| Lumen | 457 | 16.6% | – |
| Windstream | 396 | 14.4% | – |
| Verizon | 238 | 8.7% | – |
| T-Mobile | 175 | 6.4% | – |
| AT&T | 150 | 5.5% | – |
| Onvoy | 117 | 4.3% | – |
| Charter | 49 | 1.8% | – |
| Frontier | 48 | 1.7% | – |
| Bandwidth | 40 | 1.5% | – |
| Telnyx | 9 | 0.3% | – |
| Dish | 9 | 0.3% | – |
“Other CLEC / VoIP” is not one company: it is every holder outside the national carriers counted together, which is what resellers and app-based numbers look like in the records. This is allocation, not subscribers.
Spam complaints naming Iowa codes
FTC Do Not Call complaints where the caller ID shown was a Iowa number, 28 Sep – 30 Oct 2026 (33 days). Caller IDs on spam calls are routinely faked, so these are complaints about the code, not calls proven to come from it.
How Iowa got its codes
3 in the 1940s, 2 in the 2000s. Each code after the first was split off from or overlaid on one already in service.
- 1947 319 goes into service.
- 1947 515 goes into service.
- 1947 712 goes into service.
- 2000 641 goes into service, split from or overlaid on 515.
- 2001 563 goes into service, split from or overlaid on 319.
Time zones
Iowa is in Central time.
Frequently asked about Iowa area codes
How many area codes does Iowa have?
5 in service. They are 319, 515, 563, 641 and 712.
What is the oldest area code in Iowa?
319, in service since 1947. Every later code in the state was split off from or overlaid on an existing one.
What is the newest area code in Iowa?
563, from 2001, overlaying 319.
What time zone is Iowa in?
Central time.
Which Iowa area code gets the most spam complaints?
515 – 859 FTC complaints in the 33 days to 30 October 2026, 76th of 422 codes nationally. Those are complaints about the caller ID shown, and spam callers routinely fake a local-looking number, so this says the code is imitated often, not that the calls come from there.
Which carrier holds the most Iowa numbers?
No one carrier does. 37.8% of the 2,748 number blocks assigned across Iowa are held by CLEC and VoIP providers outside the national carriers – resellers and app-based numbers look like this in the records. The largest named carrier is Lumen with 16.6%. This is allocation of blocks by the numbering administrator, not a count of subscribers – people keep their numbers when they switch carriers.
Sources and verification
- NANPA – NPA Database (npa_report.csv), file date 11/01/2026, retrieved Nov 1, 2026
- NANPA – CO Code Assignment Records, All States (utilized), file updated 11/01/2026, retrieved Nov 1, 2026
- FTC – Do Not Call Reported Calls Data, 28 Sep – 30 Oct 2026, retrieved Nov 1, 2026
Figures on this page are counted from those files, not copied from other sites. Spotted an error? Request a correction. How we collect and check: methodology.