Why Do Random Numbers Call Me and How to Stop Them

Your phone rings, the caller ID shows a strange area code, and nothing but silence or a recorded robotic voice greets you. So, you may think, “Why do random numbers call me so often? You are not alone. Americans got 55 billion robocalls in 2024, according to the Federal Communications Commission (FCC). 

Below we break down the tech behind these interruptions, show you how to block them, and explain how a privacy-first VPN like VeePN limits the data that feeds future spam.

Root causes behind the wave of calls from unknown numbers

Auto-dialers, breached databases and tricky spoofing techniques all contribute to the everlasting ring-ring of strangers. Here are the five largest engines of the modern robocall business:

Automated systems scrape massive telemarketing lists

Cloud-based dialers grab spreadsheets of a million numbers, plug them into a Voice-over-IP panel, and blast out hundreds of calls per second. Due to the low cost per attempt (which cost pennies), a few pickups are sufficient to make a profit. The magnitude is jaw-dropping: in March 2025, according to the YouMail Robocall Index, there were 4.8 billion robocalls, roughly 155 million every day, with the majority being labeled as a scam or spam.

Caller ID spoofing hides the true origin

Fraudsters buy throwaway VoIP lines, then overwrite the display with whatever digits will make you trust the call: your bank’s 800-number, a local police precinct, even the IRS. The FBI warned consumers about fake “bank security” calls that used spoofed IDs to drain checking accounts, reminding the public that legitimate agencies never demand wire transfers or gift cards over the phone. 

Neighbor spoofing copies your local area code

A newer twist shows you the first six digits of your own line, tricking you into thinking a school nurse or nearby shop is ringing. One overview of caller ID spoofing notes that “neighbor spoofing” (matching the target’s area code and prefix) boosts answer rates. Attack scripts can cycle through every prefix in a ZIP code in seconds, making the calls feel almost personal.

Data breaches leak entire phone databases

When the telecoms or app vendors are hacked, the crooks will sell the raw lists in forums on the dark web and match the number with names, addresses, and even device models. The 2024 AT&T hack indicates that information on 73 million active clients were exposed, which is the threat of future spam campaigns.

Data brokers resell contact info from web forms

Any time you enter a personal phone number for a coupon or contest, it may land in a broker’s catalog and circulate to marketers. The FTC’s 2025 settlement with location broker X-Mode/Outlogic banned the firm from selling precise GPS and phone data after regulators found it was quietly piping sensitive information, including device IDs and numbers to countless third parties.

These five forces work together: breached lists feed brokers, brokers feed dialers, and spoofing disguises every ring. 

How caller ID spoofing and neighbor spoofing trick you

Caller ID spoofing relies on software that lets a dialer type any digits into the “From” field. The phone network never verifies that string, so a crook can appear to call from your bank, utility, or a local business next door. 

Neighbor spoofing goes further and copies the first six digits of your own line so that it appears even more familiar. The two schemes increase the answer rates, which makes annoying spam calls more profitable. 

What you can do:

• Never trust the number alone.
• Call the organization back on an official website number.
• Report spoofed random calls to the FCC complaint page to increase future blocking accuracy.
• Turn on “verify caller” features if your carrier supports STIR/SHAKEN tags.

Here is what may happen if you pick up strange calls: 

Risks of answering calls from unknown numbers

Picking up calls from unknown numbers seems harmless, yet it can cause:

• Identity theft. The agent might ask you to “verify” your date of birth or the last four digits of Social Security, piecing together a profile to open credit lines.
• Bank-draining voice scams. Criminals pose as fraud departments and walk victims through “secure” transfers that empty savings. There were cases where a retiree lost their life savings after believing phone scammers.
• Number validation. Simply answering tags your line as live, selling it to more spammers who make so many calls you cannot keep up. 

Call blocking features on iOS, Android devices and home phone lines

Modern phones ship with powerful shields. Why not using them:

Android devices

Settings ➝ Privacy & Security ➝ Silence unknown callers. 

This routes anything outside your contact list straight to voicemail.

iOS devices

Settings > Phone > Turn on Silence Unknown Callers.

Home phone (VoIP or copper)

Ask your provider about Nomorobo or *60 selective call rejection. Many ISPs now include free call blocking.

Robocall blocking databases

Verizon Call Filter, AT&T ActiveArmor, and T-Mobile Scam Shield label spam numbers before the first ring.

How to block spam calls and protect your number

Here are the straightforward ways to block spam calls:

• Add your line to the national do not call registry. Register at donotcall.gov in under one minute. Legitimate telemarketers must scrub that call list every 31 days. While it will not stop criminals, it slashes legit telemarketing calls within a month.
• Use call blocking apps and carrier tools. Hiya, Truecaller, and RoboKiller crowd-source bad IDs, then automatically block future calls. Carriers also push monthly updates that silence fresh spam campaigns. Combine both for layered defense.
• Keep your phone number private online.
• Avoid posting numbers on social media or Craigslist.
• Replace the real digits with a virtual line from Google Voice or MySudo when signing online forms.
• Scrub old posts with a paid lookup site (many let you opt out).
  

How VeePN helps you stay hidden from robocalls and scammers

Here are the features that VeePN brings to the table:

IP address masking

VeePN replaces your actual IP with encrypted anonymous IP, which reduces the likelihood of trackers to associate web forms with your phone number.

Encrypted Internet traffic

Using AES-256 tunneling from the VPN encryption suite, VeePN keeps sign-ups and shopping carts unreadable, so shady sites cannot grab your digits in transit.

Strict No Logs policy

Unlike many so-called “free” VPNs that monetize users’ data, VeePN stores zero connection logs, leaving robocall lists with nothing to buy.

Tracker and ad blocker

NetGuard blocks ad networks and scripts that harvest contact info. It is handy when blogs leak your number to data brokers.

Protection across all devices

One plan shields up to ten gadgets, preventing both Android and iOS leaks that spark unexpected calls.

Secure public Wi-Fi use

Airport Wi-Fi is a hotbed for IMSI-catchers sniffing phones. VeePN encrypts your session so crooks cannot pair MAC addresses with numbers.

Ready to lock down your data and hear less phone ringing? Try VeePN risk-free today, as we offer a 30-day money-back guarantee.

Written by Oliver Bennett Oliver Bennett is a dedicated cyber security content writer with a knack for breaking down intricate cyber topics into accessible and actionable insights.

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