To block all spam calls effectively in 2025, here are the best methods you can use:

1. Use Built-in Phone Features:
   • On Android: Use manual blocking by selecting the spam number in call history and choosing "Block." You can also mark calls as spam to help improve detection. Enable "Block unknown/private numbers" in settings to silence calls from numbers not in your contacts.
   • On iPhone: Enable "Silence Unknown Callers" in Settings > Phone to send calls from unknown numbers directly to voicemail.
2. Install Spam-Blocking Apps:
   • Apps like Truecaller, Hiya, RoboKiller, and Call Control can automatically detect and block spam calls. Truecaller is popular for its auto-block feature that updates regularly to catch new spam numbers.
   • These apps can block calls by creating block lists, by automatic spam detection, or by blocking calls from numbers not in your contact list.
3. Join the National Do Not Call Registry:
   • Register your phone number at the National Do Not Call Registry (donotcall.gov) to reduce telemarketing calls.
4. Use Carrier Spam Protection Services:
   • Major carriers like AT&T, Verizon, and T-Mobile offer spam call filtering services (e.g., AT&T ActiveArmor, Verizon Call Filter, T-Mobile Scam Shield) that can help block spam calls at the network level.
5. Additional Tips:
   • Report spam calls to help improve spam detection.
   • Avoid answering calls from unknown or suspicious numbers.
   • Use secondary phone numbers for online sign-ups to protect your primary number from spam.

Blocking unknown and spam calls at multiple levels - your device, apps, and carrier services - provides the best protection against spam calls in 2025.