The Current State of Nuisance Calls and Their Impact
According to data published by Japan's Ministry of Internal Affairs and Communications (MIC) in 2025, complaints related to nuisance calls reached approximately 80,000 per year - a roughly 12% increase from the previous year. The problem spans both landlines and mobile phones, and households with residents aged 65 or older are particularly vulnerable. Bank transfer fraud triggered by nuisance calls costs this demographic over 30 billion yen annually. Guide to rejecting nuisance calls Adopting blocking tools and reporting offenders has become increasingly critical. Nuisance calls originate from a wide range of number bands, including 03 and 06 area codes, 050 IP phone numbers, and 080/090 mobile numbers.
Types of Nuisance Calls and Their Characteristics
Nuisance calls come in many forms, each requiring a different response. Familiarizing yourself with the main categories helps you stay calm when an unfamiliar number rings.
Sales and Solicitation Calls
These calls push products or services such as real estate investments, insurance, or telecom plan switches. Under Article 17 of Japan's Act on Specified Commercial Transactions (Tokushoho), re-solicitation after a consumer has declined is prohibited, yet calls from different representatives or numbers persist. The National Consumer Affairs Center of Japan logs roughly 50,000 consultations per year on telemarketing. For specific refusal techniques, see How to Refuse Sales and Solicitation Calls.
Automated Voice Calls (Robocalls)
Robocalls blast pre-recorded messages to thousands of numbers at once, combining VoIP technology with auto-dialing systems to keep labor costs near zero. A telltale sign is an unnatural 0.5-to-2-second silence right after you pick up. For details, see How to Spot and Stop Robocalls.
Silent Calls (Silent Calls)
With silent calls, the line goes dead the moment you answer. They are often caused by call center predictive dialers that run out of available agents, but they can also signal stalking or attempts to confirm whether someone is home. See The Truth Behind Silent Calls and How to Handle Them for more.
Fake Survey Calls
These calls open with "Could you answer a quick survey?" and gradually extract personal information. Some impersonate legitimate research firms, making them hard to spot. The harvested data is sold to list brokers and recycled for further nuisance calls or bank transfer fraud.
Call Blocking on Smartphones
Modern smartphones have built-in call blocking features that are highly effective against nuisance calls. Review the steps for your OS below, and consider pairing them with IP phone security tools for comprehensive protection.
iPhone
Tap the offending number in your call history and select "Block this Caller" at the bottom. You can manage your block list under Settings > Phone > Blocked Contacts. On iOS 17 and later, the enhanced "Silence Unknown Callers" feature automatically sends calls from numbers not in your contacts straight to voicemail.
Android
Long-press the number in your call history and choose "Block number." If you use the Google Phone app, its built-in spam detection warns you about known nuisance numbers in real time. Steps vary by manufacturer - check your device's settings for "Block" or "Call rejection." Samsung devices offer a "Smart Call" feature that auto-displays caller information and enables blocking.
Landline Nuisance Call Countermeasures
Landlines have fewer built-in defenses than smartphones, but combining several methods can still block nuisance calls effectively.
- Number Display: NTT's caller ID service (400 yen/month before tax) shows the incoming number so you can screen unknown callers. Pairing it with "Number Request" - which auto-rejects withheld numbers - boosts effectiveness.
- Nuisance Call Rejection Service: After receiving a nuisance call, a simple dial operation registers the number for automatic rejection going forward. Up to 30 numbers can be stored (700 yen/month before tax).
- Phones with Built-in Spam Protection: Models from Panasonic, Sharp, and others play a warning message ("This call is being recorded") before connecting, and automatically record conversations - both strong deterrents.
- Tobira Phone: A dedicated filtering device that plugs into your landline and cross-references incoming numbers against a regularly updated database of known spam callers.
Carrier Blocking Services
Each major carrier offers its own nuisance call blocking service. Because filtering happens at the network level, there is minimal impact on your handset's battery or performance.
Major Carrier Services
- NTT docomo "Nuisance Call Stop Service": Blocks up to 30 registered numbers for free. Adding "Anshin Security" (220 yen/month) enables automatic spam detection.
- au "Spam Message and Call Block": Links to a spam database and displays warnings on incoming calls (330 yen/month). Includes auto-block functionality.
- SoftBank "Spam Call Block": Automatically identifies spam callers and shows a warning (330 yen/month).
- Rakuten Mobile: The Rakuten Link app includes call rejection at no extra charge.
Third-Party Call Filter Apps
In addition to carrier services, third-party spam filter apps offer even higher detection rates. Community-driven reporting keeps their databases up to date rapidly. Combining multiple layers of protection can dramatically reduce the number of nuisance calls that get through.
How to Report Nuisance Calls
Reporting malicious callers not only helps you but also protects others. Before filing a report, gather the following information for a smoother process.
- Caller's phone number: Copy the exact number from your call history
- Date and time: Record when the call came in
- Summary of the call: Note what was said
- Company or individual name: Write down any names the caller gave
Where to Report
- Police Consultation Hotline (#9110): For non-emergency consultations; connects to your local prefectural police.
- Consumer Hotline (188): Connects to your nearest consumer affairs center for advice on sales and solicitation calls.
- MIC Telecom Consumer Consultation Center (03-5253-5900): Handles complaints about telecommunications services.
- Reporting Tokushoho Violations: You can submit information about illegal telemarketing through the Consumer Affairs Agency website.
Habits That Prevent Nuisance Calls
Prevention is just as important as blocking. Review which services have your phone number on file and avoid casually entering it on sweepstakes or survey sites. Once your number reaches a list broker, multiple telemarketers will start calling. Make it a habit to let unknown numbers go to voicemail and call back only after confirming the message - this alone significantly reduces the burden of dealing with nuisance calls.
Prioritizing Your Nuisance Call Defenses
You don't need to implement every countermeasure at once. Follow this priority order for the most efficient results.
Start Here (Free)
- Use your smartphone's built-in call blocking: Block each nuisance number on the spot.
- Enable anonymous call rejection: Automatically blocks withheld-number calls. Set up your carrier's number notification request service.
- Don't answer unknown numbers: Let voicemail handle it - legitimate callers leave a message.
- Search the number on our site: Before returning a missed call, look up the number to check who it belongs to.
Next Steps (A Few Hundred Yen per Month)
- Install a spam call filter app: Auto-blocks known nuisance numbers from a cloud database.
- Subscribe to your carrier's blocking service: Network-level filtering with no impact on your device.
Landline-Specific Measures
- Activate Number Display: See who's calling before you pick up.
- Install a spam call blocking device: Automatically filters known nuisance numbers on your landline.
Measuring the Effectiveness of Your Defenses
After implementing countermeasures, check their effectiveness regularly. Most spam filter apps display statistics on blocked calls and their origins. Tracking monthly block counts gives you an objective picture: a declining trend suggests your number is being dropped from spam lists, while an increase may mean it has appeared on a new one - prompting you to add further defenses. Refer to How to Use Spam Call Databases for tips on combining multiple tools, and review How to Report Nuisance Calls so you're ready to act quickly if you encounter a particularly malicious caller.