Area code 443 – Maryland
443 has served Maryland since 1997, split from 410. All but a handful of its 786 number blocks are allocated (785 of 786), so it is effectively exhausted. No carrier dominates: Verizon 29.2%, Other CLEC / VoIP 24.7%, AT&T 15.4%. It shares its geography with overlay codes 410, 667, so local calls take all ten digits. 803 FTC complaints named a 443 caller ID in the 33 days to 30 October 2026, putting it 98th of 422 codes with five or more complaints.
- State
- Maryland
- In service since
- 1997
- Time zone
- Eastern
Who holds 443 number blocks
Share of the 785 assigned NXX blocks (99.9% of the 786 possible), across 26 carriers. This is share of number blocks, not of subscribers.
- Verizon29.2%
- Windstream19.5%
- AT&T15.4%
- T-Mobile15.3%
- Lumen9.6%
- Other CLEC / VoIP5.4%
- Bandwidth2.3%
- Onvoy1.8%
- Comcast1.3%
- Peerless0.3%
- Telnyx0.1%
Spam complaints naming 443
FTC Do Not Call complaints where the caller ID was a 443 number, 28 Sep – 30 Oct 2026 (33 days). Caller IDs on spam calls are frequently spoofed, so these are complaints about the code, not calls proven to originate in it.
Rate centers in 443
NANPA allocates number blocks to rate centers and records their names abbreviated to ten characters, so these are NANPA's codes rather than place names – CHAMPAURBN is Champaign-Urbana, NWYRCYZN01 is a New York City zone. We show them unchanged instead of guessing at the full names. Showing the largest 5 of 81.
Timeline
- 1997 443 goes into service, split from or overlaid on 410.
More about 443
Separate pages for the questions that need their own answer: what time it is there, what the complaint data says, who holds the number blocks, and how the code compares with the one it shares its area with.
Frequently asked about 443
What state is area code 443?
Maryland. It covers the same area as 410/443/667.
Can I still get a 443 number?
Only from recycled stock. 785 of the 786 available blocks are already allocated, so new numbers in the area normally come from the overlay codes (410/443/667).
Is a call from 443 a scam?
Not by itself. 443 drew 803 FTC complaints in the 33 days to 30 October 2026, 98th of 422 ranked codes – mid-pack or lower. Spam callers spoof caller IDs, so the only useful check is the full number.
Which carrier owns 443 numbers?
Verizon holds the largest share of assigned number blocks at 29.2%. The rest is spread across 3 other carriers. This is share of number blocks, not of subscribers – people keep their numbers when they switch carriers.
Do I need to dial 10 digits in 443?
Yes – ten digits for local calls in 443, because it shares its area with another code.
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, 25 daily files 28 Sep – 30 Oct 2026, retrieved Nov 1, 2026
NANPA dialing note for this code: “10D”. Reviewed by the data desk. Spotted an error? Request a correction.