An unknown number is calling me: what to do step by step
You keep getting calls from a number you don't recognise. Learn how to work out who's calling, check the number before answering and protect yourself from spam.
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An unknown number is calling me: what to do step by step
Calls from numbers you haven't saved are more and more common. Before answering or calling back, it pays to check who's behind them: the NoCall community keeps a large database of user reports on phone numbers.
1. Don't answer with your details
If you decide to pick up, listen first. Don't say your full name, don't confirm your date of birth, address or IRD number, and don't share codes that arrive by text. A legitimate caller will say who they are without asking for sensitive details upfront.
2. Look the number up on NoCall
NoCall's database holds a large catalogue of numbers identified by the community. For each number you can see its risk score, category and comments from other users:
- Risk score — from 0 (safe) to 100 (dangerous).
- Category — spam, telemarketing, scam, debt collection, surveys.
- Comments — what other users who got the same call reported.
3. Read the prefix
The first digits give you instant clues about the type of call:
- 020, 021, 022, 027, 028, 029 — New Zealand mobile.
- 03, 04, 06, 07, 09 — landline area codes (03 South Island, 04 Wellington, 09 Auckland and Northland...).
- 0800, 0508 — free-call numbers, usually businesses and services.
- 0900 — premium-rate number: calling it costs extra.
- + and a code other than +64 — international call: check the country before calling back, it could be expensive.
4. Decide: call back, block or ignore
- Low risk and a plausible reason — call back as normal.
- Spam or pushy telemarketing — block the number and report it on NoCall. The Marketing Association's voluntary Do Not Call register can reduce calls from its member companies, but scammers ignore it, and there's no government do-not-call list in New Zealand.
- Possible scam — don't call back; if you've already given out details, contact your bank and report it to NZ Police on 105.
Consumer Protection's Scamwatch explains how to spot, check and report scams.
5. Protect yourself going forward
Turn on your phone's spam filter and the NoCall app to identify incoming calls automatically. If the call felt suspicious, also read our situation guides.
Should I answer a call from an unknown number?
You can answer, but never share personal or bank details. If the call matters, they'll leave a message or call back. Afterwards, look the number up on NoCall to see whether other users have reported it.
How can I find out who called me from an unknown number?
Look the number up on NoCall: you'll see its risk score, category (spam, telemarketing, scam), network and comments from other users who got the same call.
Is it dangerous to call back an unknown number?
It can be: premium-rate numbers (0900 in New Zealand) and some international numbers charge high rates when you call them. Always check the number on NoCall before calling back.
Sources and review
Reviewed:
Numbering, carrier tools, and reporting procedures can change. Verify sensitive steps with the linked primary authority.
Article details
Editorial content reviewed by NoCall with practical context for spotting suspicious calls and messages.
Received a suspicious call?
Look up the number in NoCall before sharing data, calling back, or clicking any link.
Search a phone number or a company name (Spark, Spark and One NZ...) to check if it has been reported as spam.