I've been receiving calls that appear as "Unknown" or "No Caller ID," but I haven't answered any of them yet. Is there a way for an ordinary phone user to discover the real number behind the call, or can only the phone company or law enforcement do that?
4 Answers
If the calls are threatening, abusive, or happen repeatedly, keep a record of the dates and times and contact your phone provider. They may offer call tracing or blocking services. In serious cases, the carrier can cooperate with law enforcement, although they generally won’t disclose the caller’s identity directly to a customer.
When a call is placed, the network carries information that phones use to display the caller ID. If the caller blocks or omits that information, your phone will show something like “Unknown” or “Private Number.” Some carrier systems, switchboards, and emergency services may still have access to network-level details, but normal phones can’t reveal them.
Usually, no. A caller can withhold their number, and caller ID information can also be spoofed, so the number shown on your phone isn’t reliable proof of where the call actually came from. Phone companies and law enforcement may be able to trace the call through carrier records, but that information generally isn’t available to ordinary users.
There can be legitimate reasons for hiding caller ID, including calls from shelters or other sensitive services. Because of that, carriers don’t provide a universal way for anyone to uncover blocked numbers. Be cautious about answering or calling back unknown callers, since displayed caller ID can be forged.

Related Questions
How to Build a Custom GPT Journalist That Posts Directly to WordPress
Fix Not Being Able To Add New Categories With Intuitive Category Checklist For Wordpress
Get Real User IP Without Installing Cloudflare Apache Module
How to Get Total Line Count In Visual Studio 2013 Without Addons
Install and Configure PhpMyAdmin on Centos 7
How To Setup PostfixAdmin With Dovecot and Postfix Virtual Mailbox