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Jul 10, 2026 • 4 min read
Who Called from (520) 637-XXXX?
Search (520) 637-XXXX Numbers
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Phone Numbers: (520) 637-XXXX
Recently Searched Numbers in the 520 Area Code
About the (520) 637 Prefix
The (520) 637 prefix serves Tucson, Arizona, United States. Phone numbers in this exchange follow the format (520) 637-XXXX. The primary carrier assigned to this prefix is T-MOBILE USA INC..
(520) 637 Geographic Info
- Primary City
- Tucson
- State
- Arizona, United States
- Primary Carrier
- T-MOBILE USA INC.
Other Prefixes in the 520 Area Code
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Frequently Asked Questions
What area code is (520) 637?
(520) 637 is a telephone prefix in the 520 area code, which serves Tucson, Arizona, United States.
Where is the (520) 637 prefix located?
Phone numbers with the (520) 637 prefix are located in Tucson, Arizona, United States. The primary carrier for this prefix is T-MOBILE USA INC..
What carrier uses the (520) 637 prefix?
The primary carrier assigned to the (520) 637 prefix is T-MOBILE USA INC.. However, numbers may be ported to other carriers over time.
How do I look up a phone number with the (520) 637 prefix?
Enter the full 10-digit number (e.g. (520) 637-XXXX) into ClarityCheck's reverse phone lookup to instantly see the owner's name, address, social profiles, and more.