Learn how to block spam calls and messages on Android and iPhone, activate DND services, use spam-blocking apps, and find official solutions worldwide.
How to Block Spam Calls and Messages Permanently: A Complete Guide
Spam calls and unwanted text messages can be frustrating, especially when they interrupt your work, disturb your personal time, or put your privacy at risk. Although there is no guaranteed way to block every spam call and message permanently, you can significantly reduce them by using your phone’s built-in security features, official government services, and trusted spam-blocking apps.
In this guide, you’ll learn how to block spam calls and messages on Android and iPhone, activate Do Not Disturb (DND) services in India, and explore official spam-prevention options in other countries.
How to Block Spam Calls and Messages on Your Phone
The easiest way to reduce spam is to combine your phone’s built-in filters with your mobile network provider’s spam-blocking services.
1. Activate the Government DND Service in India
The Telecom Regulatory Authority of India (TRAI) provides a system that allows mobile users to restrict unwanted commercial communications. In India, this service is associated with the National Customer Preference Register (NCPR), commonly known as the DND service.
How to Activate DND on Your Mobile Number
You can register your preferences through the following methods:
By SMS: Send an appropriate DND preference message to 1909. Check your telecom operator’s current instructions for the correct format, as START 0 may not be the applicable format for every registration method. By calling: Dial 1909 from your mobile phone and follow the instructions to register your communication preferences. Through your telecom provider: You can also check your operator’s official website or app for available DND registration options.
Important: DND helps restrict commercial communications covered by applicable regulations, but it does not block every unwanted call. Fraudulent calls, scam messages, and communications that fall outside the restrictions may still reach you.
2. Turn On Spam Call Protection on Android
Most Android phones include features that help identify suspicious callers and filter unwanted calls. The exact settings may vary depending on your phone manufacturer and dialer app.
How to Block Spam Calls Using Google Phone
Follow these steps if you use the Google Phone app:
Open the Phone app.
Tap the three-dot menu in the top-right corner.
Select Settings.
Open Caller ID & spam.
Turn on See caller ID & spam.
If available, enable Filter spam calls.
Your phone can now identify many suspected spam callers and filter calls according to the available settings.
Keep in mind that spam detection is not perfect, and some unwanted calls may still get through.
3. Silence Unknown Callers on iPhone
iPhones include a feature that can help reduce interruptions from callers who are not saved in your contacts.
How to Enable Silence Unknown Callers
Open Settings on your iPhone.
Go to Apps > Phone on newer iOS versions. On some older versions, you may find Phone directly in Settings.
Select Silence Unknown Callers.
Turn the feature on.
Depending on your iOS version, the exact menu wording may differ.
This feature silences calls from certain unknown numbers and sends them to voicemail. However, it can also affect legitimate calls from delivery agents, new customers, or people whose numbers you have not saved.
If you regularly receive important calls from unfamiliar numbers, review your recent calls and voicemail before relying on this feature.
4. Enable Spam Protection for Text Messages
Spam messages can contain fake delivery notifications, fraudulent banking alerts, phishing links, and misleading promotional offers. Your messaging app may be able to identify and separate many of these messages.
Enable Spam Protection in Google Messages
If you use Google Messages on Android:
Open Google Messages.
Tap your profile picture or account icon.
Select Messages settings.
Find Spam protection.
Turn it on if the option is available.
Google Messages can use spam detection to identify suspicious messages and move them into a spam folder.
Avoid clicking links in unexpected messages, even if they appear to come from a bank, courier company, or government department.
Filter Unknown Senders on iPhone
To separate messages from unknown senders:
Open Settings.
Select Apps > Messages on newer iOS versions, or open Messages directly in Settings on some older versions.
Look for the available message-filtering options.
Enable the appropriate filtering feature if supported by your iOS version.
Depending on your version of iOS, you may also find filtering options inside the Messages app itself.
Filtering unknown senders helps organize messages, but it does not necessarily block them. Review filtered messages occasionally so you do not miss important notifications.
5. Use a Trusted Spam-Blocking App
If your phone’s built-in protection is not enough, a third-party caller identification app may offer additional filtering options.
Consider Using Truecaller
Truecaller is a popular option for identifying unknown callers and detecting suspected spam numbers.
Depending on your device, location, and subscription plan, its features may include:
Identifying suspected spam callers.
Blocking numbers reported by other users.
Automatically blocking selected categories of unwanted calls.
Managing blocked numbers and spam reports.
Some features may require a paid subscription or additional permissions.
Before installing any caller identification app, review its privacy policy and permissions carefully. Be especially cautious about granting access to contacts, call history, or messages.
6. Official Ways to Reduce Spam Calls in Different Countries
Different countries have their own systems for reducing unwanted telemarketing calls. These services usually allow consumers to register their numbers or manage their communication preferences.
The following table lists important official resources for readers in different countries.
Country
Official Service
How to Register
United States
National Do Not Call Registry
Visit donotcall.gov
or call 1-888-382-1222 from the number you want to register.
United Kingdom
Telephone Preference Service (TPS)
Register through tpsonline.org.uk
or contact TPS through its official website.
Canada
National Do Not Call List (DNCL)
Register through the official DNCL website
or use the contact details published there.
Use the DND registration process through 1909 or your telecom operator’s official channels.
United States: National Do Not Call Registry
Consumers in the United States can register eligible phone numbers with the National Do Not Call Registry. This helps limit covered sales calls from legitimate telemarketers.
However, registration does not stop every call, including many scam calls and certain exempt communications.
Official website: https://www.donotcall.gov/
United Kingdom: Telephone Preference Service
The Telephone Preference Service allows eligible UK consumers to register their numbers to reduce unsolicited live marketing calls covered by the service.
Registration is available through the official TPS website. Be cautious of unofficial websites that charge a fee for a free registration service.
Official website: https://www.tpsonline.org.uk/
Canada: National Do Not Call List
Canada’s National Do Not Call List allows consumers to register their phone numbers to reduce unsolicited telemarketing calls covered by Canadian rules.
Some organizations and types of calls may be exempt, and the list does not eliminate fraudulent calls.
Official website: https://lnnte-dncl.gc.ca/
Australia: Do Not Call Register
Australian consumers can register eligible phone numbers with the Do Not Call Register to reduce unsolicited telemarketing calls and marketing faxes covered by the applicable rules.
Registration does not guarantee that every unwanted or fraudulent call will stop.
Official website: https://www.donotcall.gov.au/
India: TRAI DND Service
Indian mobile users can register their communication preferences through the DND system. If unwanted commercial calls or messages continue, users can report them through the applicable complaint channels provided by their telecom operator or TRAI.
Official information: https://www.trai.gov.in/
7. Use Your Mobile Network Provider’s Spam Protection
Mobile network providers may offer additional tools to identify, filter, or block suspicious calls. Availability and pricing depend on your carrier, plan, and location.
AT&T ActiveArmor
AT&T offers ActiveArmor security features for eligible customers in the United States. Depending on the plan and device, these features may help identify or block suspected spam and fraud calls.
Check the official website for current features and eligibility:
https://www.att.com/security/
Verizon Call Filter
Verizon Call Filter offers caller identification and spam-related protection features for eligible customers. Available features may differ between free and paid versions.
T-Mobile provides Scam Shield features to help customers identify and manage suspected scam calls.
Some customers may be able to activate Scam Block by dialing #662#, although availability and activation methods can change. Check the official T-Mobile website for the latest instructions before using a short code.
Official website:
https://www.t-mobile.com/benefits/scam-shield
8. Extra Tips to Reduce Spam Calls and Messages
Even after activating DND and spam filters, a few additional precautions can help reduce unwanted communications.
Avoid Sharing Your Phone Number Publicly
Avoid posting your personal mobile number on public websites, social media profiles, and online forms unless necessary. Publicly available numbers can attract unwanted calls and messages.
Never Reply to Suspicious Messages
Do not respond to suspicious SMS messages or click unexpected links. If a message claims to come from a bank, delivery company, or government department, verify it through the organization’s official website or app.
Block and Report Repeat Offenders
Use your phone’s blocking feature to block recurring spam numbers. Report suspicious calls and messages through your carrier or the official reporting service available in your country.
Do Not Share OTPs or Banking Details
Legitimate customer support representatives should not ask you to disclose sensitive authentication codes or passwords to verify your identity. Never share an OTP, banking PIN, or password with an unknown caller.
Conclusion
Blocking spam calls and messages permanently is not always possible, but combining several protective measures can make a noticeable difference.
Start by registering for your country’s official Do Not Call or DND service. Then activate spam protection on your Android phone or iPhone, filter suspicious text messages, and consider a trusted caller identification app if needed.
Most importantly, remain cautious with unknown callers and unexpected links. Spam filters can help reduce interruptions, but staying alert is still one of the best ways to protect your privacy and avoid scams.
Frequently Asked Questions (FAQs)
1. How can I block spam calls and messages permanently?
There is no single method that blocks every spam call and message permanently. You can reduce them by activating your country’s DND or Do Not Call service, enabling your phone’s spam filters, blocking repeat offenders, and reporting suspicious communications.
2. How do I activate DND in India?
In India, you can use the 1909 DND registration process or your telecom operator’s official channels to register your communication preferences. Follow the current instructions for your operator rather than assuming one SMS format works for every registration method.
3. Does DND block all spam calls?
No. DND primarily restricts commercial communications covered by the applicable regulations. Scam calls, fraudulent messages, and certain exempt communications may still get through.
4. How do I block spam calls on Android?
Open the Google Phone app, go to Settings > Caller ID & spam, and enable the available spam identification and filtering options. Menu names and features may vary by device.
5. How do I stop unknown callers on an iPhone?
Open Settings > Apps > Phone and look for Silence Unknown Callers. Enable it to silence certain calls from numbers that are not recognized. Remember that legitimate callers may also be affected.
6. How can I block spam SMS messages?
Enable Spam Protection in Google Messages on supported Android devices. On an iPhone, use the available unknown-sender filtering options. You can also block and report individual numbers when necessary.
7. Is Truecaller safe to use?
Truecaller can help identify suspected spam calls, but its privacy implications depend on the permissions you grant and the service’s current practices. Review the privacy policy, permissions, and available subscription terms before using it.
8. Does the US National Do Not Call Registry stop scam calls?
No. The registry helps limit covered telemarketing calls, but it does not block every scammer or illegal caller. Use your phone’s spam protection and report suspected fraud when appropriate.
9. Why do I still receive spam calls after registering for DND?
Spam calls may continue because some communications are exempt, scammers may ignore regulations, and caller ID information can be spoofed. Report persistent unwanted commercial communications through your telecom provider’s official complaint process.
10. What is the best way to reduce spam calls worldwide?
The most practical approach is to combine your country’s official Do Not Call or DND service with your phone’s built-in spam protection. Keep your software updated, avoid sharing your number unnecessarily, and never disclose sensitive information to unknown callers.
