Check the address the email has come from, and the address it directs you to, if it's sending you elsewhere. Sometimes these are really close to the original but not quite. In the recent IRD case, it came from alerts.ironline.ird.govt.nzd@nz.public.com.
Any time someone contacts you out of the blue and offers you something, it's worth being wary.
Most reputable companies won't ask you for your personal details, including your password or your credit card details, over email.
If someone is threatening something, such as account disconnection, that's often a sign of a scam, too.
Keep payments within online trading and booking sites.
Netsafe says it's also worth being wary of requests that are just a bit unusual. Scammers try to use payments that can't be traced such as pre-loaded debit cards, gift cards that can be used online, iTunes cards or money transfer systems.
If it's an organisation you normally deal with and you're not sure, ring the organisation in question and ask. You can also contact Netsafe for free advice.
It's better to take some time at the outset to ensure you're not being fooled, than to have to spend weeks or months chasing money lost through a sneaky scam.
Jeremy Tauri is an associate at Plus Chartered Accountants.