Where and How to Report Nuisance Calls in Japan

Why Reporting Nuisance Calls Matters

When you receive a nuisance call, it is tempting to just ignore it. However, reporting is not only about protecting yourself - it is a socially valuable act that helps shield others targeted by the same number. As reports accumulate, police and regulatory agencies can identify malicious operators and pursue administrative sanctions or criminal prosecution. Combining reporting with call blocking methods makes your defense against nuisance calls far more effective.

The appropriate reporting channel depends on the nature of the call. Calls involving fraud or threats should go to the police; aggressive sales calls to a consumer affairs center; telecommunications-related issues to the Ministry of Internal Affairs and Communications (MIC); and call blocking requests to your carrier. This article walks through each channel's role and the specific steps for filing a report.

Before diving in, here are the four main reporting channels side by side.

Reporting to the Police

When to Call 110

In the following high-urgency situations, call 110 without hesitation:

• You received a threat such as "Pay up or we will hurt you"
• You just transferred money after receiving a scam call
• You are receiving persistent calls that appear to be stalking behavior
• The caller threatened to come to your home

When calling 110, briefly explain when, from where, and what kind of call you received. Call logs and recordings will be useful for any subsequent investigation. Emergency numbers are toll-free and available 24 hours a day.

Police Consultation Hotline #9110

For non-emergency consultations, use the police consultation hotline #9110. Dialing #9110 connects you to the consultation desk of your prefectural police. Hours are generally weekdays 8:30 - 17:15, though they vary by prefecture. Depending on your situation, the operator will advise you on how to file a formal report or what steps to take next. According to the National Police Agency, police handled roughly 2.77 million consultations in 2025, and calls about nuisance callers and suspected fraud are part of that total.

Information to prepare before calling:

• The caller's number (check your call history)
• Date, time, and frequency of the calls
• What was said (be as specific as possible)
• Any call recordings you may have
• The nature of the harm (financial loss, emotional distress, etc.)

Refer to the legal guide to call recording to ensure your recordings are preserved properly. Call recording is generally treated as legal in Japan when done by one party to the conversation, and it gives the police a solid record of what was said.

Cybercrime Consultation Desks

Nuisance calls that are combined with internet or email schemes - such as phone-based phishing lures - can also be reported to your prefectural police's cybercrime consultation desk. Tactics that blend SMS phishing with phone calls may be treated as cybercrimes. Since the 2020s there have been reports of caller ID spoofing used to impersonate public agencies, so cases requiring technical investigation benefit from the cybercrime desk's expertise.

Reporting Sales and Telemarketing Calls

Where you report a persistent sales or solicitation call depends on what was said and how aggressive the caller was. A sales call that keeps coming after you have declined is likely to breach the ban on repeat solicitation in Article 17 of the Act on Specified Commercial Transactions, which means a report can become the basis for administrative action.

Choosing Where to Report a Sales Call

• Sales calls with threatening language: report to the police (#9110 or 110). Telling you that refusing will bring consequences may amount to extortion
• Calls that keep coming after you refused: report to the Consumer Hotline 188. This can support administrative action for breaching the Act on Specified Commercial Transactions
• Solicitations for real estate investment, insurance, or telecom contracts: you can also pass information to the supervising agency (the Financial Services Agency or the MIC)
• Operators that keep calling from different numbers: report to both the police and a consumer affairs center, and ask that the pattern be treated as organized misconduct

When you report a sales call, write down the company and product name the caller gave, the phone number, and the date and time of each call. A recording of the call is especially useful. Try the approaches in how to refuse sales calls first, and move to reporting if the calls still do not stop.

Consulting a Consumer Affairs Center

Consumer Hotline 188

For complaints about aggressive sales calls or telemarketing fraud, call the Consumer Hotline at 188 (pronounced "i-ya-ya" in Japanese). Dialing 188 automatically connects you to your nearest consumer affairs center, where trained counselors can mediate disputes with businesses on your behalf.

Cases where a consumer affairs center is especially helpful:

• You were pressured into a contract over the phone
• A company keeps calling despite your refusal
• You want to exercise your cooling-off rights
• You received a sales call from an unidentified business

Consultations are free and confidential. As complaints accumulate, they form the basis for administrative action against offending businesses. Consultations you file are logged in PIO-NET (a nationwide consumer information network), and a concentration of complaints against a single business can trigger regulatory enforcement. Reviewing how to refuse sales calls in advance can help prevent further harm.

What Consumer Affairs Centers Can Do

Consumer affairs centers go beyond simple advice - they have the authority to mediate between consumers and businesses. This includes assisting with cooling-off procedures for telemarketing contracts, challenging unfair charges, and negotiating contract cancellations. Understanding your rights under the Specified Commercial Transactions Act before consulting will help you receive more targeted support.

Reporting to the Ministry of Internal Affairs and Communications

MIC Telecommunications Consumer Consultation Center

Complaints related to telecommunications services can be filed with the MIC's Telecommunications Consumer Consultation Center (03-5253-5900). Hours are weekdays 9:30 - 12:00 and 13:00 - 17:00. Applicable cases include:

• Nuisance calls impersonating a telecom carrier
• Mass dialing via IP phone abuse
• Unauthorized use of phone numbers
• Dissatisfaction with a carrier's response

The MIC has the authority under the Telecommunications Business Act to issue business improvement orders or revoke registrations. Reporting is especially effective for nuisance calls originating from 050-prefix IP phone numbers. Information from users is one of the triggers the ministry relies on when judging whether such action is needed.

Reporting to Your Carrier

How to Report Nuisance Calls to Carriers

Major carriers such as NTT Docomo, au (KDDI), SoftBank, and Rakuten Mobile all maintain nuisance call reporting channels. Reported numbers are added to each carrier's spam database and used to display warnings or block calls for other subscribers.

Using your carrier's spam call filter service lets you automatically block calls from reported numbers. See how to block nuisance calls for details on each carrier's offerings. Reporting to your carrier protects not just you but also other users targeted by the same number.

Third-Party Call Filtering Apps

In addition to carrier-provided services, third-party filtering apps aggregate user reports to identify and flag nuisance callers in real time. Combined with caller ID, these apps let you instantly check incoming call information.

Preparing for an Effective Report

Preserving Evidence

Having evidence on hand makes the reporting process faster and more productive. Build a habit of recording the following:

• Call history screenshots - capturing date, time, and caller number
• Call recordings - using your phone's built-in recorder or a dedicated app
• Notes - documenting what was said, who the caller claimed to be, and what they demanded
• Related SMS or emails - saving any SMS or email messages connected to the calls

Review how to preserve evidence of phone harassment and understand the conditions under which recordings are legally admissible. Always back up evidence in multiple locations and never alter the original data.

Choosing the Right Reporting Channel - A Quick Guide

If you are unsure where to report, use the following decision criteria:

• Immediately after a threat or fraud - Call 110 (emergency)
• Criminal but not urgent - Call #9110 (police consultation)
• Aggressive sales calls or contract disputes - Call 188 (Consumer Hotline)
• Telecom fraud or number abuse - Call the MIC (03-5253-5900)
• Call blocking setup - Contact your carrier
• Internet-linked scam - Contact the cybercrime consultation desk

If your situation fits multiple categories, report to each relevant channel. Each desk covers a different range of problems, so telling several of them keeps anything from slipping through. See also the police consultation guide for phone fraud.

Summary

Reporting nuisance calls is a vital step toward both personal protection and broader public safety. Route criminal calls to the police, aggressive sales calls to a consumer affairs center, telecom-related issues to the MIC, and blocking requests to your carrier. Keeping thorough records of every incident dramatically increases the effectiveness of your reports. Every individual report contributes to the larger effort to stamp out nuisance calls.