To prevent spam calls on your cell phone, enable your carrier's built-in spam filter and register your number on the FCC's Do Not Call list. In 2026, over 45 billion robocalls are projected annually, but simple steps can cut them by 80% or more. Start with your phone's silence unknown callers setting.
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Most major national carriers now offer free spam-blocking services as part of their compliance with the FCC's STIR/SHAKEN caller ID authentication mandate. In 2026, all large networks provide an opt-in or auto-enabled feature that flags or blocks likely spam calls before they reach your phone. For example, one of the large networks automatically screens calls and labels them “Spam Risk” or “Scam Likely.” To activate it, open your phone’s dialer or carrier account app and look for “Call Filter,” “Spam Block,” or a similar toggle. The FCC reports that STIR/SHAKEN has cut illegal robocalls by roughly 65% since its rollout, but only if consumers enable the blocking layer.
Use Built-In Phone Tools
Every modern smartphone — whether from a leading premium smartphone maker or a budget provider — includes a setting to silence unknown callers. On most devices, this sends calls from numbers not in your contacts straight to voicemail without ringing. In a 2025 consumer survey, 72% of users who enabled this feature reported a noticeable drop in daily spam interruptions. To find it, go to your phone’s Settings > Phone > Silence Unknown Callers (or similar). You can also set up “Do Not Disturb” schedules that allow only favorite contacts through. These free tools are your first line of defense and require no extra downloads.
Register on the Do Not Call List
The National Do Not Call Registry, managed by the FCC and the Federal Trade Commission, remains one of the simplest ways to reduce telemarketing calls. As of 2026, over 250 million numbers are registered. While it does not block illegal robocalls (which ignore the list anyway), it stops legitimate telemarketers from calling you. Registration is free at donotcall.gov and takes effect within 31 days. The FTC estimates that registered numbers receive up to 35% fewer telemarketing calls than unregistered ones.
Consider Third-Party Call-Blocking Apps
If carrier and phone settings aren’t enough, reputable third-party apps can add another layer. Look for apps with large community-based spam databases that update in real time. A 2026 study by a consumer advocacy group found that users who combined a carrier filter with a third-party app blocked an average of 92% of unwanted calls. When choosing an app, check permissions: a good app only needs access to your call log and contacts, not your messages or location. Avoid apps that request unnecessary data. Below is a comparison of typical features offered by top-rated call-blocking apps in 2026:
| Feature | Free Tier | Premium Tier |
|---|---|---|
| Spam number database | Yes (community-sourced) | Yes (curated + updated daily) |
| Reverse phone lookup | Limited (5 per month) | Unlimited |
| Auto-block robocalls | Basic | Advanced with custom rules |
| Voicemail transcription | No | Yes |
Note that no app can stop all spam, but combining tools dramatically reduces annoyance.
Best Practices for Voicemail & Unknown Numbers
Spam callers often use voicemail phishing — leaving fake messages about debts or package deliveries. To protect yourself:
- Never press a number or call back an unknown number that leaves a suspicious voicemail.
- Set your voicemail password (default passwords are often 0000 or 1234).
- Enable “Transcript Preview” so you can read the message without listening — many spam calls are automatically flagged.
- If you answer a spam call, hang up immediately; do not engage or say “yes” (voice recordings can be misused).