Sent the same day, a short thank-you keeps you in mind while they decide. Fill in the boxes and the email writes itself.
Filled in with an example. Type in the boxes to make it yours.
Subject: Thank you: Senior Analyst interview
Hi Tom,
Thank you for meeting me on Tuesday about the Senior Analyst role. I enjoyed hearing about the plan to replace the claims platform next year.
My last project was a platform replacement of the same size, and I enjoyed that work.
I am keen on the role and look forward to hearing from you.
Kind regards,
Sam Hollis
Send it the same day or the next morning, to each person who interviewed you if you have their details. Keep it short: this is a thank-you, not a second interview.
The specific detail is what makes it land. Name something they told you, not a general compliment about the company.
More on this: NZ job interview questions and preparation
Keep every letter with the job it belongs to: jobtracker.co.nz is free while you're between jobs. See all the letter templates.