You can block spam calls far more effectively than most people realize, and almost none of it requires a paid app. The scam-call industry works on volume — auto-dialers spraying millions of numbers and waiting for answers. Your goal isn’t to stop every call from existing; it’s to stop your phone from ringing for them. These seven settings, layered together, get most phones down to a stray call or two a month.
Block Spam Calls With Your Phone’s Built-In Filter
Both platforms ship a filter that most people never switch on. On Android, open the Phone app → Settings → Caller ID & spam, and enable both “See caller and spam ID” and “Filter spam calls.” Suspected spam then goes straight to voicemail without ringing. On iPhone, Settings → Phone → Silence Unknown Callers sends any number not in your contacts, recent calls, or Siri suggestions to voicemail silently. Legitimate callers leave a message; robots almost never do.
Turn On Your Carrier’s Free Blocking
The major carriers all run network-level scam blocking that flags or drops known scam numbers before they reach you — but some of it is opt-in. Look for T-Mobile’s Scam Shield, AT&T’s ActiveArmor, or Verizon’s Call Filter in your account app; the basic tier of each is free. Because carriers see calling patterns across the whole network, they catch spoofed-number campaigns that on-device filters miss.
Join the Do Not Call Registry
Register your number free at donotcall.gov. It won’t stop criminals — scammers ignore the law by definition — but it cuts the legal telemarketing layer, which thins overall volume and makes the remaining calls easier to treat as hostile. Registration never expires, and it takes about a minute.
Never Answer, Never Press 1
Answering a spam call — even to yell at it — marks your number as “live” and reliably increases future calls. Pressing a digit to “be removed from the list” is the same trap. If you don’t recognize a number, let voicemail handle it. And if a call claims to be your bank or a government agency demanding urgent action, hang up and dial the organization directly from its official website; the FTC’s unwanted-calls guide covers the current scam scripts.
Block and Report the Repeat Offenders
For numbers that keep coming back, use the block option right in your recent-calls list — on both platforms it’s a tap away. On Android, choose “Block/report spam” so the number also feeds Google’s shared spam database; iPhone offers similar reporting through supported carrier apps. Blocking individual numbers is whack-a-mole against spoofers, but it works well on persistent legitimate-ish pests like aggressive sales lines.
Guard Your Number Like an Address
The long game is starving the lists. Stop entering your real number on shop loyalty forms, contest entries, and random website sign-ups — that’s where spam lists are born. A free Google Voice number makes a fine “public” number for forms and marketplaces while your real one stays quiet. It also becomes a handy filter: calls to the Voice number are, by definition, from someone who got it off a form.
When a Paid App Is Actually Worth It
If you’ve layered everything above and still get pounded — common for numbers that have been on breach lists for years — a dedicated screening app like Nomorobo, RoboKiller, or Hiya adds one more net. They maintain live databases of active scam campaigns and can answer robots with a bot of their own so the call never touches you. Two cautions before paying: read the privacy policy, since call-screening apps by nature see your call metadata, and try your carrier’s paid tier first — it usually costs the same and integrates deeper. Most people who apply the free layers never need this step at all.
What to Expect Afterward
Layer the on-device filter, the carrier service, and the registry, and the change is dramatic within a couple of weeks — the calls mostly die in voicemail or never arrive. Check the voicemail tab occasionally for the rare legitimate stranger, then adjust: if a school or clinic keeps landing there, add them to contacts and they ring through normally.
Spam calls and phishing texts travel together, so it’s worth learning to spot phishing scams and tightening your phone privacy settings while you’re at it. More practical guides live on the Tips & Tricks homepage. You’ll never block spam calls to absolute zero — but you can make your phone ring only for humans you actually want to hear from.