Manchester, New Hampshire
Area code 603 phone validation
Calling or texting a list of 603 numbers? Check every number first: valid or dead, mobile, landline or VoIP, and the carrier it is on now.
Start 7-day free trial →What validating 603 numbers tells you
- ✓Valid or dead. Disconnected and unassigned 603 numbers are flagged before your dialer or SMS tool reaches them.
- ✓Mobile, landline or VoIP. Know which numbers can take a text and which are desk phones or app numbers.
- ✓Carrier. The carrier each number is on now, which can differ from the company that was first given the prefix because numbers are ported.
Who holds 603 prefixes
Companies holding the most 603 prefixes (NPA-NXX blocks) in the NANPA utilized-codes report. This is who was assigned the number blocks, not who serves each number today: a number can be ported to any carrier, which is why a live check matters.
| Consolidated Comm Of No. New England | 246 prefixes |
| Bell Atlantic Mobile | 74 prefixes |
| Paetec Itel | 58 prefixes |
| Mcimetro Access Transmission Services | 45 prefixes |
| Comcast Ip Phone | 40 prefixes |
| Omnipoint Miami E License | 38 prefixes |
68 of 752 603 prefixes are held by companies that commonly supply numbers to VoIP and texting apps.
Places served by 603
Manchester, Nashua, Concord, Derry, Dover, Portsmouth, Merrimack, Salem.
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Questions
Where is area code 603?
603 serves Manchester, New Hampshire, including places such as Nashua, Concord, Derry. Time zone: Eastern Time (ET).
Does a 603 number mean the person is in New Hampshire?
Not always. People keep their numbers when they move or switch carriers, and VoIP numbers can be assigned anywhere. The area code tells you where the number was first assigned, not where the person is today.
What does validating a 603 number tell me?
Whether the number is valid or dead, whether it is a mobile, landline or VoIP line, and the carrier it is on now, from live carrier data.
Does TrueSearch check Do Not Call lists?
No. TrueSearch does not check the National Do Not Call Registry, state DNC lists or litigator lists yet. Run those checks separately where they apply.
603 prefix pages
Area code 603 reference: places, prefixes and local time
This guide is general information, not legal advice. TrueSearch for Business checks validity, line type and carrier from licensed telecom data. It does not check the National Do Not Call Registry, state DNC lists or the FCC Reassigned Numbers Database. Not a consumer reporting agency; not for FCRA purposes.