How to Stop Spam Calls: What Actually Reduces Them

You cannot block your way out of spam calling — campaigns rotate through number pools faster than anyone can tap 'block'. What works is layering: reduce how often your number is dialled, filter what reaches your screen, and report the source so carriers can act upstream.

Layer 1 — Your phone's own settings

• iPhone: Settings › Apps › Phone › Silence Unknown Callers. Anything not in your contacts, recent outgoing calls or Siri suggestions goes to voicemail without ringing.
• Android: Phone app › Settings › Caller ID & spam. Enable spam filtering, and optionally Call Screen on Pixel devices so Google answers first.
• Both platforms let you block a number from the recent-calls list — worth doing for repeat offenders even though pools rotate.

Layer 2 — Carrier-level filtering

Most major carriers now offer network-side call filtering, often free at the basic tier. Because it operates before the call reaches your handset, it catches campaigns your phone never sees. Check your carrier's app for a 'call filter', 'scam shield' or 'call protect' feature and turn on the strictest setting you can live with.

Layer 3 — Do-not-call registration

Registering will not stop criminals, who ignore the list by definition, but it does remove you from the legitimate telemarketing pool — often a meaningful share of the volume. In the US, register with the FTC's National Do Not Call Registry; in Canada, the CRTC's National DNCL; in the UK, the TPS.

Layer 4 — Report, do not just block

Reports are what let regulators and carriers trace a campaign to its originating provider. In the US, file with the FTC and the FCC; in the UK, with Ofcom and Action Fraud; in the EU, with your national telecoms regulator. Include the number, the date and time, and what the caller claimed.

Layer 5 — Reduce your exposure

• Never enter your real number in giveaway forms, quizzes or coupon offers — these are lead-generation funnels.
• Use a secondary or virtual number for deliveries, marketplaces and one-off signups.
• Remove your number from social profiles and public business listings you no longer need.
• Do not answer, press keys, or say 'yes' to unknown calls — every interaction marks your number as live.
• Opt out of data brokers where you can; many honour a removal request even though they will not stop collecting.

What to do when one gets through

1. 1Let it go to voicemail. Real callers leave messages.
2. 2If you answered, share nothing and hang up — you owe a cold caller no explanation.
3. 3Identify the number afterwards so you know whether it was a nuisance or an impersonation attempt.
4. 4Block it, then report it.

Realistically, layered defences cut volume dramatically rather than to zero. The goal is a phone where an unknown ring is unusual enough to be worth checking.