The 3-layer defense: pick your country + carrier + device for the exact steps. 20+ carriers covered, plus iOS/Android settings, do-not-call registries, and the 5 best third-party blockers honestly compared.
Free basic; Call Filter Plus $3.99/mo per line
Free version: blocks high-risk calls, screens spam, shows caller ID for unknown numbers. Plus version adds caller ID for personal calls, spam-number lookup, and the ability to create a personal block list with risk scoring.
Built into iOS 13+. Routes calls from numbers not in your Contacts, Recents, or Siri Suggestions directly to voicemail. The caller hears your voicemail greeting; you see the missed call in Recents.
Free registration. Telemarketers must stop calling within 31 days. Does NOT block scam calls, political calls, charities, debt collectors, surveys, or robocalls from companies you have a business relationship with.
Register on National Do Not Call Registry→Report illegal robocalls and unwanted calls. The FCC investigates patterns and fines violators. Also see fcc.gov/robocalls for educational resources.
File a complaint →If layers 1-3 still let too many through, add a dedicated blocker app. Ranked by editorial score — we honestly note the trade-offs.
AI-driven robocall blocker with answer bots that waste scammers' time. Largest paid market share; FTC partnership data shows ~99% block rate on known scam patterns.
Default caller-ID provider built into Samsung Smart Call and AT&T Call Protect. Hiya's caller-ID database is among the largest globally.
World's largest crowd-sourced caller-ID database — 350+ million daily active users. Strong outside the US (dominant in India, Middle East, Africa).
One of the originals (2013). Uses "simultaneous ring" tech on landlines to intercept robocalls before the first ring completes. Mobile uses a more standard blocking approach.
Voicemail-focused approach: known robocallers hear "this number has been disconnected" — they update their lists and stop calling. Visual voicemail included.
STIR/SHAKEN is the FCC-mandated caller-ID authentication framework deployed by all major US voice providers since 30 June 2021. It cryptographically signs outgoing calls so receiving carriers can verify the caller ID is legitimate. It has reduced spoofing significantly — about 95% of voice traffic among top US Tier-1 carriers now uses A-level attestation.
But it doesn't stop robocalls entirely because:
See our deep-dive: STIR/SHAKEN explained →
If strangers are calling YOU asking why you called THEM — or angrily saying you scammed them — spammers are using your phone number as their spoofed caller ID. This is a different problem from incoming spam, and unfortunately there's no permanent fix:
BubblyPhone outbound calls are STIR/SHAKEN A-attested — your caller ID is cryptographically signed, so calls from BubblyPhone don't get flagged as spam on the receiving end (unlike personal mobile lines, which often do).